Question

Should I create a unique App ID per application for the App Store?

Answer 1

In general, the "Bundle identifier" should be unique for each applications. This doesn’t mean that there should be unique "App ID" created for each application. Its not necessary to create different App IDs for different applications. You can use a single App ID with asterisk(*) as wild-card character to specify different bundle identifiers.

The Doc says,

If you are creating a suite of applications that will share the same Keychain access (e.g. sharing passwords between applications) or have no Keychain Access requirements, you can create a single App ID for your entire application suite utilizing a trailing asterisk as a wild-card character.

In these wild-card situations, you’ll simply replace the asterisk with whatever string you wish in the CF Bundle Identifier field in Xcode.