Database / Sqlite on iPhone

Here's a tutorial discussing how to create and read a simple sqlite database on iPhone.

There are several ORM efforts to make it easier to easier to access the db without writing SQL. For example: Persistent Object

Beta Testing on the iPhone

The current supported method for beta testing iPhone apps is through Ad Hoc distribution. You need the Device ID of each iPhone that you want to test your app on, then sign the apps.

I had trouble getting the ad hoc distribution profile to show up under "Code Signing Provisioning Profile" in Xcode, until I tried the following:
"Apple's instructions have two steps reversed. The step that says "In the project window, select the Distribution Active Configuration from the overview popup and set the Active SDK to Device..." must be done FIRST, before you can choose your provisioning profile." (original thread)