Only support Android 5.1+ Dual Sims Phone due to Google native support. Any prior to Android 5.1, do not use it. =========================== Ringtone Randomizer is easy to use. It allows you pickup any song file as a ringtone. Just a few steps you can set up playlists of ringtones, and get different ringtone after each incoming calls. - Fast and light app - Support unlimited ringtones - Support to scan all files in devices, no need to put ringtone into specific folders - Support Android 7.1 App