Q: How do I migrate my drills to the Pro Version or a new phone?
A: The drills are stored in a user accessible directory on the phone.
The exact location of the directory is listed on the About screen
(Menu:About) under Storage. Copying the files will transfer the drills.
Q: I get a broken drill error. What can I do?
A: Most likely the memory on your phone is going bad.
The app keeps several backups of each drill to deal with this. You can make them (in)visibile
To solve your problem, make the backups visible. Then remove the broken drill and rename
one of its backups to not have "[xxx]" at the end of its name. Note that renaming really just copies the drill.