Alpha releases are in flux. This means that they are not feature complete and, in some cases, not even backwardly compatible. The intended audience is friendly testers that are willing to contribute data for the proof-of-concept analytics and algorithmic stages to follow.
Here's where we're at on features:
Supported Android versions:
As of March 15, 2016, the latest version is alpha-0.68:download alpha-0.68
The Android app is currently in early testing and will soon be available on Google Play. In the interim, click the link above and follow these simple instructions to install the app. The non- Google Play install process contains a number of warnings that you have to acknowledge in order to proceed. On a Galaxy S4, the prompts look like the following: