OnSong is designed to show both chords and lyrics. However there are times when you might find chords are not appearing as chords, that chords are not aligning with lyrics, or that you are unable to transpose a song's key. This can happen because chords are not being detected or denoted properly.
OnSong supports two ways to denote chords. You can either place chords in square brackets within your lines of lyrics like this:
[C]This is my [G]song and it [F]isn't very [C]long
You can also place chords over lyrics and use spaces to align the chords above lyrics like this:
C G F C This is my song and it isn't very long
The key is not to combine these two methods. For instance, if you place chords in brackets above lyrics, the chords will not line up with the lyrics. If you are using chords over lyrics and have a square bracket anywhere in the song content, chord detection for chords over lyrics is disabled which can cause the chords to no longer be found.
We cover a lot of this in our overview tutorial video that you can watch here: http://onsongapp.com/videos/tutorials/overview
You can learn more about the OnSong and ChordPro file formats here: