Google officially announced the Tango smartphone alongside Lenovo earlier this year, and although the first phone to come with Tango software inside, known as the PHAB2 Pro, is not yet available, Google have seen fit to launch a dedicated app for Tango phone that allows you to see a gallery of images that were taken utilizing Tango's advanced technology. The app, simply called Tango, is also meant to allow a Tango-powered smartphone take advantage of and launch/access a user's favorite AR apps and experiences.
That being said, you'll need to have a Tango phone to actually install the app, as it's not compatible with any other Android phones at the moment, and it's likely that it won't be either. Alternatively, you should also be able to download the app onto the Project Tango tablet that Google released a while back, if you have one of those in your possession. Although it is quite possible for Google to add more content to the application as it gets older and once the Tango phone is actually available, right now it appears to be an exploration app which only lets you look around a vibrant-colored planet and at close up shots of its wildlife inhabitants, as well as a collection of other locations as you can see from the screenshots below, although it doesn't seem to list off any of the names for what users can actually explore.
If the app catches your eye and makes you more interested in the PHAB2 Pro, the device is said to be launching next month, so the wait to get a hold of a phone which can install the Tango app is not far off. The PHAB2 Pro will come with a 6.4-inch display that has a Quad HD resolution and it's powered by a specially optimized Qualcomm Snapdragon 652 processor along with 4GB of RAM and 64GB of internal storage space for apps, games, videos, pictures, and music. It's also got support for expandable storage via a microSD card slot and it comes running on Android 6.0 Marshmallow, although it will have an upgrade to Android 7.0 Nougat at some point.