Orpheus
About Orpheus (Google play) FREE
About Orpheus (Orpheus-app.com)
- No user guide, Orpheus-app.com includes instructions
MobileSheetsPro
About MobileSheetsPro (Google play) (Price as of 9/17: $12.99)
About MobileSheetsPro (Zubersoft.com)
MobileSheetsPro User Guide