So far, I haven't seen a really reliable database app that does what I want, and I don't think I'm even that picky! Here's a list of apps that I've found so far:
iDB Datamaster (three different versions)
AppCreator Database Manager
and several SQL-based apps.
What I like most about these various apps is the encryption and protection of Tap Forms, the photo-adding feature of StoreIt, and the flexibility of AppCreator when customizing fields.
Any suggestions? Developers, here's your chance to make a LOT of people happy.