Worship Songs in ChordPro format. I use this repo to have a history of my edits and to share the work I have put in with others.
Originally I was using PerfectGuitarSongBook for iOS but as of iOS 14 the development has stalled as of February 2019.
I am in the process of migrating my library to SongbookPro for iOS which is in active development. SongbookPro features database backup, but I will still maintain changes to individual song files.