I received an e-mail this morning from a user of DeepDishDesigns GigBook, which has been removed temporarily from the App Store, as version 1.6 of the app (a rather new update) has a bug which deletes songs from the program. DeepDishDesign is working on an emergency update (in fact, it has been submitted), but in removing the app from the App Store, it keeps current (and new users) from downloading the program and experiencing the same issue. The app will re-appear when it has been updated without the bug. This is about the best customer service you could expect from a developer under such conditions.
They also uploaded an instructional video of how to restore a backup of your music files to DeepDishDesigns GigBook: http://www.youtube.com/watch?v=vqHRCNnHI44
I wanted to use this opportunity to recommend two strategies for anyone that uses a PDF music reader:
A) You should have two readers on your device, so that if something ever does happen to a program (e.g. a bug on an update, or issues with a new OS), you can fall back on another app.
B) You should open a Dropbox account and keep copies of your scores in Dropbox, so they can be accessible, even if your “original” is deleted from an app.
So if you are a forScore owner, it is wise to have unrealBook or GigBook on your device–or any combination of those programs. Even if you never use that other app, $4.99 is a small price to pay for peace of mind. I have personally had issues with PDF music readers in the past, and having a backup app and accessibility of my files on Dropbox has meant no loss of instructional time or the loss of use of the iPad because of a “broken” app.