Periscope, Twitter’s latest acquisition, has launched today on the App Store. For those who haven’t been following the news, Periscope is a company that Twitter bought before the rise in popularity of Meerkat, a live streaming app. Periscope also lets you live stream video from your iPhone, but, according to early reviews, it’s cleaner, faster, and obviously more integrated with Twitter’s social graph – which was unceremoniously cut off from Meerkat.

Mat Honan has a good story on Periscope:

Fire up the app, launch the camera, and the app tweets out a message (if you want it to) that you have gone live. Simultaneously, a notification fires off — with that little look-at-me whistle — to everyone following you on Periscope. As they join in, they can comment on what you’re doing. And because it has super-low lag time — or latency, to use the term of art — people watching can comment on your actions more or less as they happen. It means that people watching the video can change the course of what’s happening. They can chime in with questions or comments, and all the while tap-tap-tap on the screen to send a stream of hearts to the broadcaster. Don’t want comments? Fine, you can turn them off. If you choose, you can let the video live on Persicope’s servers afterwards, where it will stay for 24 hours before disappearing forever. Or you can choose to let your video be purely ephemeral, living only in the moment and then gone forever. It is delightfully fun.

Joanna Stern’s article, however, really hit close to home for me:

Maybe I should be thankful. Periscope’s biggest promise lies in those times when life is far from boring. Whether it be a breaking news situation or a friend’s traumatic experience, there are times when peeking in and watching a live story unfold makes the most sense. While it’s bound to be abused, this new way of communicating could bring us closer than any photo or recorded video could.

I experienced that this week. My friend Drew Olanoff, who has been suffering from Hodgkin’s Lymphoma, just had a stem-cell transplant. He’s been using Periscope to stream (or “‘scope”) from his hospital room, updating his friends and followers on his progress. Every day, he shows the board that lists his blood stats and flips the camera around—by tapping on the screen—so we can see how he looks.

Like Joanna, I don’t know if my life is exciting enough to warrant a daily dose of live streams. But then again, before Twitter and Facebook and Instagram, most of us didn’t think we’d be inclined to share so much about our daily lives either. Reading how Drew is using Periscope reminds me of when I was stuck there doing a stem cell transplant, and how I wished I could update all my friends and readers at once in a simple, natural way. Sure, I could send selfies to different iMessage threads and I could tweet text and pictures, but the idea of a real-time live stream is much more powerful. And Periscope is pretty cool: I came across some questionable streams in the Home tab, but the app is fast, polished, and, indeed, a window into the world of others.

Live streaming isn’t new. But this new take on the category – fast, integrated, mobile – comes at an interesting time. Periscope is free on the App Store.

Earlier today, Twitter announced that Foursquare will soon power location tagging across the company’s suite of apps. In a video shared today, Twitter showed how location data by Foursquare will be embedded into Twitter for iPhone to allow users to tag specific places instead of using Twitter’s previous (coordinate-based) location database.

Coming soon! We’re working with @foursquare so you can tag specific locations in Tweets: https://t.co/MwlLz5Pfvq pic.twitter.com/jATzXvbuV6

— Twitter (@twitter) March 23, 2015

This is an interesting move for a couple of reasons. First off, Twitter has chosen to rely on a third-party for a precise database of places instead of building its own from scratch – and they cleverly picked Foursquare, which has amassed an impressive collection of 65 million places in six years. I’m curious to see if Twitter will use this newfound power to enhance ads and offers on the service (imagine Foursquare-powered deals available in a Twitter card).

Second, Twitter needs to improve their local discovery features. With a richer collection of places, Twitter could unlock previously unseen contextual, local features that wouldn’t be possible with simple coordinates (think venues like concerts and museums or spots like a cafe in Rome).

Foursquare’s Dennis Crowley writes:

In addition to building the world’s most accurate place database, we’ve learned how to see buildings the way our phones see them — as shapes and sensor readings on the ground rather than boxes viewed from space. We’ve built software that can understand when people move through, stop within, and then move on from these shapes — whether the shapes are places, neighborhoods or cities. And we’ve built search and recommendation algorithms that get smarter as they learn about the shapes you choose to spend time in and the shapes you simply pass through. You’ll hear us talk about these things as “stop detection,” “snap-to-place,” “the Pilgrim engine” — they’re the pieces that make us confident that no matter where you’re standing in the world — whether it’s your own neighborhood or a far-away city you’re visiting for the first time — we can raise your awareness of the best experiences nearby and help you find places you’ll love.

Smart move from Twitter, and long overdue.