Hello ciderfish -
it sounds like you may need to update the operating system on your device. The app can run on Android OS 4.1 (Jelly Bean) and above, so your device would need to be running at least that version of the Android OS.
If your device is running OS 4.1 or above and you are still running into this difficulty, please feel free to file a support case with us from under the Help tab of the site and let us know the details of your device and OS in the case and we'll be happy to look into it further.
-Craig