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].