Importing OnSong songs
OnSong is a similar app to OpenSongApp that is only available for iOS. It is one of the best alternatives for iOS users, but it does come at a price (unlike OpenSongApp which is FREE!!!!).You can share your songs with OnSong users by exporting them and you can import songs from OnSong users.
OnSong has a feature that allows exporting songs as OpenSong format, but users may also share their entire library as an OnSong backup file. These backup files are actually zip files that contain orphan songs and an SQLite database of OnSong files. The good news is that OpenSongApp can import this backup file and will then batch convert the songs into OpenSong format for you!
To do this, first copy the OnSong.backup file into your OpenSong folder. You can do this using a file manager on your Android device, or by clicking on the file, OpenSongApp will try to move it automatically for you. Once done, from within OpenSongApp, select the 'Import OnSong backup' option from the Storage menu. It will ask you to specify the backup file you just moved (it only shows files in the OpenSong/ folder). After clicking on the green tick, OpenSongApp will import any songs it finds into a folder named 'OnSong' and will convert them into OpenSong format. This will take a while, so be patient and let the process finish!