Download
On Google Play for Android, in your browser everywhere, and on the App Store once Apple has reviewed it.
T4TSpace runs in your browser at t4tspace.com/app, with nothing to install and no store account needed. One account works everywhere: the website, the Android app, and the iPhone app when it is out.
Android
The app is on Google Play, free, with nothing sold inside it. Open it on Google Play, or read what it does and what it asks of your phone.
It is not offered in countries where the law or the police target trans people. Where, and why.
iPhone
The app has been submitted to Apple and is waiting for review. Until it is out, open the site in Safari and use Share, then Add to Home Screen: it then opens like an app, and on iPhone it is the only way notifications can reach you. More about the iPhone app.
In a browser, on any device
Nothing to install, and nothing is missing: the browser version is the full service. On Android you can add it to your home screen from the browser menu.