Btty is available for iOS (Apple App Store) and Android.
For Android installation follow this procedure:
- Open btty.com
- Follow the link or scan the QR code with your Android Phone. The dowload will start automatically.
- Open "My Documents" and select "btty.apk" in the folder "Downloads".
- Change to "Settings -> security" .
- Enable "Allow Unknown sources - installation from sources other than Play Store”.
- Activate "Allow Installation" in the dialog box, then approve "App Hits".
- Finish the installation and open btty.