How Twitter Periscope Works

Kayvon Beykpour, co-Founder and CEO of Periscope
© Noam Galai/Getty Images for TechCrunch

A submarine's periscope allows its submerged passengers to see what's going on above water right away. Similarly, the Periscope app lets its users see what's going on in the world in real-time, but instead of using tubes and mirrors, the app uses the cameras embedded in most smartphones, along with the broadband networks to which the phones are connected 24/7. Most new smartphones allow users to record video, and apps are starting to emerge that take advantage of these capabilities to allow real-time video streaming.

Periscope is a new phone app that allows you to livestream your life to a network of friends and strangers alike. As a viewer, you can watch people visit historic sites, attend events, walk in their own neighborhoods or just carry about their daily business all over the world. Viewers can respond to the people sharing their experiences via chat or send hearts to show approval. Livestreaming is the next step beyond sharing messages, links, pictures and pre-recorded video on social media. It enables anyone with a smartphone or tablet and the app to quickly and easily become a live broadcaster.


Periscope was founded by childhood friends Kayvon Beykpour and Joe Bernstein in February 2014. The two had previously created and run the mobile and social app company Terriblyclever, which they sold to Blackboard in 2009. Periscope was purchased by Twitter in January 2015, and the app launched on March 26, 2015, adding live video to Twitter's real-time text service.

The app has already allowed users to broadcast a myriad of things, from the mundane to the newsworthy. And other users can open the app and view any number of streams from the point of view of the broadcasters, who are everyday joes and celebrities alike. It has its limitations, but Periscope is fast becoming a fun way to explore the world, or share your own, through your smartphone.


The Periscope App

Periscope used to require a Twitter to use the app, but now you can log in with your phone number if you prefer.
© Chris Jackson/Getty Images

To use Periscope, you must first download the app. Initially, Periscope required a Twitter account for signup/login, and you can still log in that way, but now if you don't have a Twitter account (or just don't want to use it for whatever reason), you can also sign up using your phone number.

When you first open the app, it goes to the main watch screen, also accessible via a TV icon link at the bottom of the screen. This page lists livestreams of the people you are following (if any) and their recent broadcasts from the last 24 hours, including anything you've streamed recently. You simply touch any of the livestreams to start viewing immediately, and touch the X in the upper right to end viewing.


Aside from the TV icon, other bottom-screen buttons include a globe that takes you to the Global page, a camera that takes you to the Broadcast Now page and a cluster of people that takes you to the People page.

The Global page lists live streams from users all over the world. As with the main page, just touch one of the items on the list to begin viewing the stream, and hit the X at the top right to exit back to the previous screen.

While viewing any live broadcast from either the main or Global page, a stream of chats will scroll up from the bottom left, and you can participate if you like. Just type some text in the window that says "Say something..." and hit "Send." If a lot of people are chatting, you might see a lock icon and the text "Broadcast too full" in the chat window. If you click it, you'll receive a notification that there are a lot of people watching and only early joiners can chat. The app can also reportedly revert to only allowing users the broadcaster follows to chat once a large enough number of people are viewing.

You will see animated, color-coded hearts that you or others are sending rising from the bottom right. You send them by tapping the screen. Hearts are the equivalent of the Facebook like, except that you can send as many as you want. In Periscope, your popularity is ranked by number of hearts received, not number of followers.

To bring up more information while viewing a stream, swipe to the right or click on the person icon on the bottom right that shows number of people viewing at the moment. Either action brings up an information screen with the title of the stream, the broadcaster's location on a map (if allowed), the streamer's name and handle, a follow icon, and "Share" and "Hide Chat" (or "Show Chat," if you've already hidden it) buttons. Below that, all the current viewers are listed, as well as the number of viewers. At the bottom are a "Report Broadcast" icon and link. "Hide Chat" is useful if you find that the chats are obscuring your view of the video. The "Share" button allows you to suggest the current stream to your followers (either selected ones or all of them) via a push notification. If you get one of these notifications while you're in the app, you can either dismiss or view the suggested stream with a touch. And "Report Broadcast" is for reporting inappropriate content.

If you select a stream that's already ended, you can hit the play icon to start viewing the older stream. You'll see the video, the chat stream and the hearts, although you won't be able to chat. You can, however, send hearts while watching a replay. These videos will disappear 24 hours after broadcast.

The Broadcast page allows you to start streaming whatever your phone camera is seeing (and whatever your microphone is hearing). We'll elaborate on broadcasting in a bit.

The People page lets you select who to follow. The first users on the list are people you follow on Twitter who are also on Periscope, and the people below that are the "Most Loved" Periscope users. At the top left, there is a search icon to help you find people by name or username, and at the top right, there is a single person icon that takes you to your own user profile page.

Your profile page shows your username, the number of hearts you have accumulated, your bio (from Twitter, if you don't edit it within the app) and links to lists of who you are following, who is following you, users you have blocked and your past broadcasts. You can also adjust a couple of settings there and get to the Help Center, Terms of Service and other useful information. A logout link is at the bottom of this screen.


Broadcasting With Periscope

Periscope’s pre-broadcast and viewing screens
Images courtesy of Periscope

Periscope lets you start broadcasting live video from your phone after a few button clicks. Just open the app and hit the camera icon to get to the Broadcast Now page. The first time you go here, you will have to allow access to the microphone and camera, but after that, you just type in text to name the broadcast (or leave it blank to settle for "Untitled") and hit the "Start Broadcast" button to begin streaming with the default settings.

Before you start, there are small icons above the "Start Broadcast" button that allow you to change your broadcast settings. These include an arrow to toggle location sharing on and off, a lock to make your broadcast private and let choose which of your followers can view it, a chat icon that allows you to toggle between everyone being able to chat and only users you follow being able to chat, and a Twitter icon that lets you choose whether your session will be posted to Twitter. All currently default to the most public setting.


If you do not disable posting to Twitter, a post with a link to the video will appear on your Twitter feed. If a Periscope user clicks the link from their phone, it will open the app and go to the video (unless they're not allowed to view it due to settings or blocking). If a non-user clicks it, it will invite them to get the Periscope app. People can view public Periscope videos on the web via Twitter. The app also sends a notification to your Twitter followers that you're streaming, provided they allow push notifications.

To respond to chat messages, you can tap a comment, hit the reply button and quickly type a response, or you can respond verbally. If you block someone, the service posts a message to the chatroom saying you blocked the user.

While broadcasting, tapping the screen twice flips between the front-facing and rear-facing camera. To stop broadcasting, swipe down and hit the "Stop Broadcasting" button that appears.

There's no time limit to your streams, and your videos are saved for 24 hours. The app also gives you a chance to download your video to your phone when you finish streaming. If you do a very long video that surpasses your phone's storage space, you just won't be able to save the video. When a user (or you) replays your video, the chat messages and hearts still appear, but if you save it to your phone, it saves the video without the extras. During the 24-hour retention window, the info page for the video lets you hide the chats or delete replay entirely. After the time expires, or after you disable replay, the info page is still there and still shows the title, location, username and list of viewers.

Community guidelines for using Periscope are included in the terms of service, which you can get to within the app. Not following the guidelines can get your content removed or even get your account suspended. Rules include not streaming copyrighted, pornographic, overly graphic, abusive or misleading material (including various types of spam, phishing or other malicious content). They also do not allow anything that contributes to criminal activity or anything that discloses certain types of private information about another person. On graphic material, they will make allowances for anything newsworthy or with scientific, educational or artistic merit. The user retains the rights to their content, but the Periscope terms of service gives Twitter and their partners a non-exclusive license to use all of the content for a variety of purposes.


Uses for Periscope

Some of the potential uses for Periscope are much like those for any service that allows you to upload video. You can use it to show people your kid's recital, cute videos of your pets, or anything else that is going on around you, but in real-time instead of from the past. And since Periscope lets you save down the resulting videos, you can upload them to YouTube or another video hosting site later, if you wish.

The live nature and social features of Periscope also allow for interactions between the broadcaster and viewers that you don't get with sites like YouTube and Vimeo. Sure, you can post comments on them, but with Periscope, you can make comments via chat and the broadcaster might see and respond to them in real time.


You can use Periscope to follow the live actions of your friends, official entities and celebrities. And, provided you're one of the early viewers, you may even be able to interact with them via chat. Early in the life of Periscope, Jimmy Fallon broadcast a live rehearsal, Aaron Paul broadcast a live performance from his living room and Benjamin Millepied broadcast backstage from the Paris Ballet during a performance of Swan Lake [source: Medium]. Retired Canadian astronaut Chris Hadfield has even used it to broadcast educational videos and musical numbers to his followers [source: Feltman].

One woman, LA-based artist Amanda Oleander, even became Periscope's first star, or "most loved," in April 2015, after being sent millions of hearts [sources: Brown, McGarry]. She has been overtaken by a few others since then, but as of summer 2015, she's still in the top five with more than 12 million hearts.

There are also more serious possible uses, such as citizen journalism. The idea for Periscope was actually sparked when protests sprang up in Taksim Square in Istanbul in 2013. Periscope co-founder Kayvon Beykpour was planning a trip there at the time, and he looked for news to determine whether it was safe to travel there (his hotel happened to be near the protests). He realized that he could read about the unrest on Twitter in real-time, but couldn't view it, even though there were likely lots of people there with smartphones. And the traditional news stories weren't giving him the on-the-street information he needed, either [sources: Pierce, Shontell].

We could get (and have gotten) streams from protests, natural disasters, elections, sporting events and other newsworthy occurrences from around the globe. The 24-hour life of the streams just makes it essential that the user save any potentially important videos down for posterity.

On the day of Periscope's launch, users broadcast a fire from a gas explosion in New York's East Village in Manhattan before news crews had even arrived on the scene. Periscope users didn't actually know the details of what they were broadcasting, so professional news media filled in the gaps for people later [sources: McGarry, Popper].

Professional journalists have even taken to Periscope to provide coverage. Paul Lewis, correspondent for "The Guardian" in the U.S., livestreamed footage and interviews via Periscope from Baltimore, Maryland during the unrest that followed the funeral of Freddie Gray, who was killed in police custody [sources: Lewis, MacMillan]. And local to national news outfits have been trying out behind-the-scenes Periscope feeds [sources: KTLA 5, Lewis]. BBC Radio 2 presenter Tony Blackburn showed his users around BBC's Broadcasting House with Periscope, although the network has apparently put a temporary kibosh on doing so until they can look into any potential issues [source: Greenwood].

Periscope could also be used to get news out of areas where it's harder to provide coverage, such as countries with oppressive regimes where network television broadcasts are censored. The livestreaming site Ustream is offering a service called Ustream for Change that provides some users with cost-free and ad-free streaming service and tech support for just this purpose [sources: Fingas, Ustream]. But free apps like Periscope that require no more hardware than a phone, and at least for now do not stream ads, could make such efforts easier and more widespread.

Twitter currently has no plans to introduce advertising into Periscope streams or to create promoted videos. There's speculation that they might make money through Niche, a Twitter-acquired company that provides analytics software to social media stars and connects them with companies that might want to use them for promotions [sources: Advertising Age, Alba, Twitter Blog].


Issues and Concerns

While most people probably expect that they may be filmed during an event like a press conference, the average person walking down the street isn’t normally thinking about being broadcast online.

As with any video or social platform, there are potential issues, some of which are already being realized with Periscope.

Online harassment is common, especially if you put yourself out there on social media, and Periscope users are not immune. People can (and too often do) say vile things via chat while a user is streaming, especially female users [sources: Lorenz, Sinders]. Anyone who spews vile or hate-filled comments can be blocked immediately if you get to their chat in time. You can also scroll through the list of people who viewed a video, click on a user, go to the settings icon and choose to block them, or find and block users on the People page. Once blocked, they won't be able to find your future streams. Viewers can also block people from chatting. As of June 2015, users can report broadcasts for inappropriate content, but cannot yet report users for harassing comments.


Location sharing can potentially leave users vulnerable to stalking and other privacy violations. Fortunately, you can toggle location sharing off when you begin broadcasting if that sort of thing scares you. The initial version of the app let viewers zoom into the map to see a broadcaster's actual street location, meaning people could potentially find your exact current location or find out where you live. Fortunately, an app update fixed this and now the less stalker-friendly map zooms in to a larger geographic area [source: Baldwin].

Privacy of the people around you is also an issue. As you're walking down the street livestreaming, the people around you will not likely know they or their voices are appearing in your stream. More than before, we may all need to start assuming we're being filmed when we're out and about.

Media companies have some concerns about the potential for piracy through Periscope and other livestreaming services, since people can livestream anything, including paid events and television shows they're watching. In April 2015, HBO issued takedown notices to Periscope when some users livestreamed the "Game of Thrones" season five premier [sources: Jarvey, Panjwani]. Unlike Google's veteran video service YouTube, which has Content ID technology that detects possible pirated material in their hosted videos, as of early summer 2015, Periscope doesn't have anything that detects or prevents infringement as it's happening and instead relies on user notifications of violations of its copyright infringement policies. According to the Digital Millennium Copyright Act of 1998 (DMCA), such service providers are shielded from monetary liability provided they respond to notices of infringement by taking down or blocking the content quickly [sources: U.S. Copyright Office, Panjwani]. But livestreaming is fast and mostly temporary, so the content may already be gone by the time takedown notices are provided or acted upon.

One saving grace in the piracy arena is that Periscope is not a high-quality video affair, since the app only streams in standard definition and relies on its mostly amateur users' camerawork. As Periscope CEO Beykpour put it, "Nobody wants to watch 'Game of Thrones' on Periscope" [source: Constine].

Twitter CEO Dick Costolo caused a bit of a stir by tweeting, "And the winner is... @periscopeco," after the May 2, 2015 pay-per-view HBO and Showtime broadcast Floyd Mayweather-Manny Pacquiao boxing match [sources: Costolo, Dolcourt, Wallenstein]. He could have been referring to more official uses like HBO Boxing's Periscope broadcasts from Pacquiao's locker room on the night of the match [source: Kafka, Wallenstein]. But some people were reportedly livestreaming the event playing on their TV through Periscope and rival app Meerkat.

Periscope works with companies to take down infringing material, including 30 takedowns out of 66 requests during the Mayweather-Pacquiao fight, the rest of which ended on their own before being taken down [sources: Constine, Kafka, Sandomir]. CEO Kayvon Beykpour later tweeted, "Piracy does not excite us. Trust me, we respect IP rights & had many people working hard to be responsive last night (including myself)" [sources: Almasy, Beykpour, Hesseldahl].

Even some uses by official media are in question. The NHL warned sports media, some of whom had livestreamed footage from practices, warm-ups and other game-related events, that any such transmission within NHL arenas is against the rules without prior written permission [source: Muir].

There are other issues with Periscope that are more technical in nature. The app doesn't currently support turning your phone sideways to film in a landscape/widescreen aspect ratio, so most videos at the moment will be upright (which some people find annoying). You can film landscape, but when people turn their phones to view it properly, the chats will be sideways.

Live streaming video also might eat up all your cellular data plan's monthly bandwidth. Video is bandwidth heavy, and Periscope has no time limit for individual videos and no limit on how many times you can stream. Frequent Periscope users might start getting some pretty large bills from their cell phone companies, unless they are have unlimited data plans. And even then, their speed might start getting throttled.

Adam Leidhecker reportedly used his entire monthly data plan limit while livestreaming at the 2015 South by Southwest (SXSW) festival using Meerkat, which is estimated to use up around 4 MB per minute for streaming and 2.3 MB per minute for viewing a stream [source: Abbruzzese]. Periscope usages are likely similar. Using a WiFi connection instead of cellular is possible, especially if you're streaming from home and have a WiFi network, but user's home Internet Service Providers (ISPs) often have data caps, as well, and going over could at best get you throttled and at worst lead to overage charges or, in some rare cases, suspension of service.


Changes to the App

Aside from the location viewing changes mentioned earlier, there have been other tweaks to the app since its release. It's been updated several times and is already up to version 1.0.4 as of this writing.

Early on, there were only three icons at the bottom of the screen: the TV, camera and people icons. The main TV screen showed current livestreams, and it was reportedly hard to sort through the multitude of streams from all over the world to get to the ones you would most likely want to watch, like the streams of the people you follow.


Version 1.0.1 sorted the listings so that live broadcasts of users you follow would be at the top, and version 1.0.2 added the Global tab. Now the main viewing tab (the TV icon) shows current livestreams of those you follow as well as links to their recent streams, and the Global tab has the list of the most recent live broadcasts from strangers all over the world. Version 1.0.2 also added the ability to let you choose to only broadcast to your followers, added a Twitter verification badge, and made it easier to block offensive commenters (by tapping a comment and choosing a block option). Version 1.0.3 added the ability to see your own or other user's broadcast histories for the previous 24 hours and the ability to see if a user is live from their profile, improved the account sign up process and changed the front-facing camera's orientation as far as what viewers see. Version 1.0.4, the latest as of this writing, lets users upload or take a new profile picture (rather than just using the one from Twitter), reply directly to commenters by tapping on their comment and sign up using a phone number rather than a Twitter account.

Every update also fixes bugs and other issues, and more fixes and functionality changes are in the works. The Periscope team is reportedly working on map-based browsing that will let you find streams near you or in another area by location [source: Fingas].



Meerkat, pictured here, offers an alternative live streaming app experience to Periscope.
© Kay Nietfeld/dpa/Corbis

Periscope's one major rival is Meerkat, which came out on February 27, 2015 (a little earlier than Periscope) and was reportedly built in 8 weeks by the company Life On Air [sources: Constine, Kumparak]. Meerkat is a similar, but much simpler, livestreaming app that is available for iOS (8.0 or later) and Android devices. The Android version is a beta as of mid-2015, and Periscope is available for devices running iOS 7.01 or later, and just launched its Android app. There are other notable differences between Meerkat and Periscope. Meerkat doesn't keep your streams for any length of time, whereas Periscope saves them for 24 hours. Periscope will just send out a tweet when you start streaming (if you haven't disabled it for that video), but Meerkat will tweet that you are streaming and tweet all user comments. Periscope's comments stay in-app. Periscope's chats also reportedly appear on the screen faster, allowing for closer to real-time conversation with the broadcaster [source: Pierce]. Periscope also allows private streams whereas Meerkat does not. Meerkat was untethered from Twitter's social graph on fairly short notice around the time it was announced that Twitter had purchased Periscope, meaning that users will no longer be connected to all of their Twitter followers or people they're following automatically, although they can still log on via their Twitter credentials and Tweet that they are streaming [sources:Kumparak, Seppala].

Meerkat has released a developer platform and application program interface (API) to help developers build tools using the service. Before the launch, developers had already used a more unofficial version of the API to create analytic tools and allow for automatic YouTube uploads, among other things [source: Constine]. Meerkat also now has Facebook support.


Your choice of app might depend upon who you want to follow and what platform they've chosen. Using both is not out of the question.

Other potential rivals are YouNow and the Ustream phone apps. Recording video with a smartphone and sharing online via YouTube or Facebook could also be seen as competition, but the real-time nature of Periscope lends it to slightly different sorts of uses.


What's next?

The Periscope app’s profile view (left) and settings screen
Images courtesy of Periscope

Livestreaming from your phone is the next logical step past video sites like YouTube, and existing livestreaming sites like, Twitch and, which for the most part require a computer running special software and a webcam. Periscope makes livestreaming as easy as picking up your phone, opening an app and clicking a couple of virtual buttons. Now that we have the technology, and many of us carry it with us everywhere we go, livestreams may become ubiquitous.

Twitter reportedly paid around $86 million total in cash (and other considerations like stock options) for both Periscope and Niche, although it's unclear how much was for each one [source: Wagner]. Periscope started with only five employees and grew to thirteen as of early May 2015 [source: Constine]. Twitter's purchase of Periscope gets Twitter immediately into the video arena, and provides Periscope with the backing of a large company. It also gives Periscope the potential to tap Twitter's large, built-in user base. Already you can easily find other Twitter users who have Periscope from within the app.


Periscope's reception has been fairly positive, so far. Celebrities and news outlets have embraced it. And more than 1 million people signed up in the first 10 days after Periscope's launch [source: Constine, Wallenstein]. There's lots of entertainment to be had watching broadcasters wander their daily lives, and the interactivity component makes it even more appealing to a lot of people. A meme even quickly emerged where people often asked to see the inside of the broadcasters' refrigerators [source: Weber].

It's exciting to think about where this new technology might take us. We can watch users do anything from put on makeup to explore noteworthy sites, and it has already provided some insight into current events. It could be another one of those things that becomes second nature to a lot of people, like texting and using smartphones did before. There's no telling what sights we'll be able to see in the near future.


Lots More Information

Author's Note

I downloaded and played with Periscope as research, and it was incredibly engaging. I test-streamed my dog walking around the yard, and a few users chimed in, mostly from other countries. Being shy, I wasn't very talkative, but I did respond to a question or two. And then I watched other people's streams, including a man taking a walk in Japan and one of the "most loved" broadcasters having her blood pressure measured by an in-store machine. They and some of the others I watched were chatty and engaging, and I have to admit, when someone responds to one of your chat comments, it does give you a bit of a charge, and lends immediacy and intimacy to the whole video streaming experience. Plus the little hearts are cute. I did have to turn the sound off on my phone's Periscope push-notifications, as they got annoying really fast. But I still let them appear silently so that I won't miss anything.

The most exciting things about Periscope and similar apps are the prospects of getting live news from events as they unfold and of seeing sights all over the world that I may never see through travel. And in the future, this seems like the type of functionality that will pop up in lots more apps, or maybe even get built into a mobile OS. I, for one, am looking forward to a time when everyone has livestreaming capability and we can find footage of nearly anything. Who knows? We might even get Periscope broadcasts from space.

Related Articles

More Great Links


  • Abbruzzese, Jason. "Smartphone data plans can't keep up with live video broadcasting on Meerkat and Periscope." Mashable. March 25, 2015. (May 21, 2015)
  • Advertising Age. "Twitter Taking a Different Approach to Advertising on Vine and Periscope." May 8, 2015. (May 20, 2015)
  • Alba, Davey. "Twitter Acquires Niche, A Talent Agency For Social-Media Stars." Wired. February 11, 2015. (May 20, 2015)
  • Almasy, Steve. "Mayweather Pacquiao fight: The action is finally getting started." CNN. May 6, 2015. (May 21, 2015)
  • Apple. "App Store - Periscope." May 11, 2015. (May 21, 2015)
  • Apple. "iTunes Preview - Periscope - By Twitter, Inc." (May 14, 2015)
  • AT&T. "Estimate your monthly usage." (May 21, 2015)
  • Baldwin, Roberto. "Periscope update keeps viewers from showing up at your house." Engadget. April 2, 2015. (May 16, 2015)
  • Brian, Matt. "Meerkat is silently fixing a flaw that lets anyone hijack livestreams." Engadget. March 19, 2015. (May 19, 2015)
  • Brown, Aaron. "Up Periscope: Twitter app makes unknown 25-year-old new Kim Kardashian with 7.5m 'lovers.'" Express. April 24, 2015. (May 21, 2015)
  • Carroll, Casey. "Twitter says that Periscope for Android is on the way." 9TO5Google. April 3, 2015. (May 19, 2015)
  • Constine, Josh. "Meerkat Launches Developer Platform To Differentiate From Periscope." Techcrunch. May 6, 2015. (May 20, 2015)
  • Constine, Josh. "On Piracy, Periscope CEO Says 'There's Way More Media Attention Than Problem.'" Techcrunch. May 5, 2015. (May 16, 2015)
  • Constine, Josh. "Periscope Saw Over 1 Million Sign-Ins During Its First 10 Days." Techcrunch. April 28, 2015. (May 20, 2015)
  • Constine, Josh. "Twitter Confirms Periscope Acquisition, And Here's How The Livestreaming App Works." Techcrunch. March 13, 2015. (May 19, 2015)
  • Constine, Josh and Ingrid Lunden. "Twitter Is Pushing Celebrities And Publishers To Stop Using Meerkat." Techcrunch. April 12, 2015. (May 19, 2015)
  • Costolo, Dick. "And the winner is... @periscopeco." Twitter. May 2, 2015. (May 20, 2015)
  • CrunchBase. "Terriblyclever Design." (May 21, 2015)
  • Dolcourt, Jessica. "Periscope the big winner for Mayweather-Pacquiao pay-per-view dodgers." C/NET. May 3, 2015. (May 20, 2015)
  • Feltman, Rachel. "This app got me a lullaby from my favorite astronaut, and you can have one, too." Washington Post. March 31, 2015. (May 21, 2015)
  • Fingas, Jon. "Periscope will find live video streams near you." Engadget. May 5, 2015. (May 16, 2015)
  • Fingas, Jon. "Twitter bought a live-video streaming company." Engadget. March 13, 2015. (May 19, 2015)
  • Fingas, Jon. "Ustream starts a nonprofit program to back citizen journalists." Engadget. February 19, 2014. (May 21, 2015)
  • Golen, Jimmy. "Periscope goes back to the sea in around-the-world race." San Jose Mercury News. May 14, 2015. (May 19, 2015)
  • Greenwood, Carl. "Tony Blackburn gets slap on the wrist after using Twitter's Periscope service to broadcast live from BBC." Mirror. April 18, 2015. (May 21, 2015)
  • Hesseldahl, Arik. "Re/code on the Air: Potential Deals for Salesforce and Yelp, Preiscope Piracy and More!." Re/Code. May 10, 2015. (May 21, 2015)
  • Honan, Mat. "Twitter Chokes Off Meerkat's Access To Its Social Network." BuzzFeed. March 13, 2015. (May 19, 2015)
  • Jarvey, Natalie. "HBO Criticizes Periscope Over 'Game of Thrones' Live Streams, Issues Takedown Notices." Hollywood Reporter. April 14, 2015. (May 21, 2015)
  • Kafka, Peter. "Twitter Has a Short-Term Periscope Problem And a Long-Term Media Mess." Re/Code. May 5, 2015. (May 14, 2015)
  • KTLA 5. "Live Video: Go Behind-the-Scenes of KTLA 5 Morning News With Twitter's Periscope." April 21, 2015. (May 21, 2015)
  • Kumparak, Greg. "Twitter Starts Breaking Meerkat Features By Limiting Social Graph Access." Techcrunch. March 13, 2015. (May 19, 2015)
  • Lee, Nicole. "Periscope makes it easier to view live streams from people you know." April 8, 2015. (May 16, 2015)
  • Lee, Nicole. "Twitter's Periscope is the best livestreaming video app yet." March 26, 2015. (May 16, 2015)
  • Lewis, Helen. "Tories on Twitter, policy on Periscope, and Andrew Marr's pigeon pie." Guardian. April 19, 2015. (May 21, 2015)
  • Lewis, Paul. "The Baltimore riots: the night on Periscope - video." Guardian. April 28, 2015. (May 20, 2015)
  • Lorenz, Taylor. "Twitter's new live streaming service, Periscope, has a harassment problem." Business Insider. April 1, 2015. (May 17, 2015)
  • MacMillan, Jim. "Periscope journalism evolving in Baltimore: 'Just let the truth come out.'" #streamalism. April 28, 2015. (May 20, 2015)
  • Mallin, Noah. "Will The Next Content Revolution Be Live Streamed? How Periscope and Meerkat are Inventing the Future." Huffington Post. April 22, 2015. (May 20, 2015)
  • McGarry, Kevin. "Come Watch Periscope's First Star." Cut. April 22, 2015. (May 20, 2015)
  • Medium. "Oh the places you'll go." April 1, 2015. (May 19, 2015)
  • Medium. "Six Weeks In." May 11, 2015. (May 14, 2015)
  • Medium. "Up Periscope." (May 14, 2015)
  • Midgley, Neil. "Rolling TV election news eclipsed by Twitter, Buzfeed and Periscope." Guardian. May 3, 2015. (May 20, 2015)
  • Miller, Chance. "Meerkat announces public beta for upcoming Android app." 9TO5Google. April 15, 2015. (May 19, 2015)
  • Muir, Allan. "NHL torpedoes Periscope Twitter app in arenas; Senators savior?; more." Sports Illustrated. April 22, 2015. (May 20, 2015)
  • Nield, David. "Meerkat's Android App Is Live On Google Play." Digital Trends. May 2, 2015. (May 21, 2015)
  • Oakes, Omar. "Twitter focuses on video with Periscope purchase." MediaWeek. May 14, 2015. (May 20, 2015)
  • Panjwani, Raza. "Up Periscope: Law and Live Video in the Meerkat Era." Re/Code. May 7, 2015. (May 21, 2015)
  • Panzarino, Matthew and Alexia Tsotsis. "Twitter Buys Live Streaming App Periscope." Techcrunch. March 4, 2015. (May 19, 2015)
  • Perez, Sarah. "Twitter Is Winning The Live Streaming Battle." Techcrunch. April 16, 2015. (May 19, 2015)
  • Periscope. "Periscope iOS 1.0.3 update is on the @AppStore with new features and improvements!..." Twitter. April 28, 2015. (May 20, 2015)
  • Periscope. "You may have heard the news...." Twitter. March 13, 2015. (May 19, 2015)
  • Pierce, David. "Twitter's Periscope App Lets You Livestream Your World." Wired. March 26, 2015. (May 21, 2015)
  • Pollock, Tristan. "The live-stream video tween battle: Meerkat's still fighting, but Periscope is winning." VentureBeat. April 25, 2015. (May 21, 2015)
  • Popper, Ben. "Meerkat launches on Android before Twitter's Periscope." Verge. May 1, 2015. (May 19, 2015)
  • Popper, Ben. "There was an explosion in New York City, and seconds later I was watching it live on Periscope." Verge. March 26, 2015. (May 21, 2015)
  • Pullen, John Patrick. "Livestreaming Apps Will Totally Crush Your Data Plan." Time. April 2, 2015. (May 21, 2015)
  • Russell, Jon. "Periscope Decouples From Twitter To Let New Users Sign Up With A Phone Number." Techcrunch. May 11, 2015. (May 20, 2015)
  • San Francisco Maritime National Park Association. "Periscope Chapter 1 - Description." (May 21, 2015)
  • Sandomir, Richard. "Periscope, a Streaming Twitter App, Steals the Show on Boxing's Big Night." New York Times. May 4, 2015. (May 19, 2015)
  • Seppala, Timothy J. "Twitter's limiting a video competitor's access to its social framework." Engadget. March 14, 2015. (May 19, 2015)
  • Shontell, Alyson. "What it's like to sell your startup for ~$120 million before it's even launched: Meet Twitter's new prized possession, Periscope." Business Insider. March 26, 2015. (May 21, 2015)
  • Sinders, Caroline. "How Periscope should redesign its interface to reduce abuse." Verge. May 14, 2015. (May 16, 2015)
  • Singh, Baljeet. "Welcoming Niche to the Twitter team." Twitter Blog. February 11, 2015. (May 20, 2015)
  • Twitter. "Periscope - About Us." (May 14, 2015)
  • Twitter. "Periscope - Community Guidelines." (May 17, 2015)
  • Twitter. "Periscope - Terms of Service." (May 17, 2015)
  • Upclose. "What is upclose?" (May 19, 2015)
  • Ustream. "Ustream for Change." (May 21, 2015)
  • Ustream. "Ways to Broadcast on Ustream." (May 21, 2015)
  • Verizon. "Data Usage Calculator." (May 21, 2015)
  • Wagner, Kurt. "Twitter Paid Over $86 Million for Periscope and Niche." Re/Code. May 11, 2015. (May 20, 2015)
  • Wallenstein, Andrew. "Periscope Piracy Sets Up Grudge Match: Hollywood vs. Twitter." Variety. May 3, 2015. (May 21, 2015)
  • Weber, Lindsey. "Periscope is a deranged dreamscape full of fridges, and I love it." Daily Dot. March 29, 2015. (May 21, 2015)
  • Weil, Kevin. "Excited to officially welcome @periscopeco to the Twitter team...." Twitter. March 13, 2015. (May 19, 2015)
  • YouNow. (May 21, 2015)