In brief: Eight months after its alpha release, the first stable version of the Tor browser for Android has arrived on the Google Play store.
With more people now accessing the internet via mobile devices than desktops, an official Tor app was inevitable. While it had been possible to connect to Tor from a smartphone using the Orbot/Orfox app, it now comes built directly into the official browser---you no longer need to install the mobile proxy app Orbot separately.
Tor enables anonymous communication by redirecting traffic through decentralized relays to cover your tracks. In addition to making sure your IP address stays private, it can be used to circumvent geographical blocking, making it an extremely useful tool for journalists and activists inside countries with online restrictions.
"Mobile browsing is increasing around the world, and in some parts, it is commonly the only way people access the internet," wrote the Tor Project. "In these same areas, there is often heavy surveillance and censorship online, so we made it a priority to reach these users."
Other features in the Tor mobile browser include a blocker that prevents third-party trackers and ads from following you, fingerprint resistance that makes it difficult to identify users by browser and device information, multi-layered encryption, and the ability to access sites blocked by ISPs.
The browser is based on FireFox v60, so you get similar features such as tabbed browsing and private mode.
There's no iOS version of the browser available due to restrictions imposed by Apple. Tor recommends using Mike Tigas' Onion Browser iOS app instead. You can download the desktop version as well as the Android version of Tor here.