Can you edit/format lyrics on the web with Band Helper?
Yes, BandHelper has a web interface. You can see some screen shots in this tutorial...
http://www.bandhelper.com/tutorials/getting_started.html
...or in this demo video:
https://www.youtube.com/watch?v=3PuFO1OHFV0&list=PLimpKVYo7g9yJHMgiJHvhALhSO5qm8eIF&index=1