What are all the things an app ID is used for in iOS apps, what is the downside of making it alphanumeric?

We'd like to change the App ID that we currently use without changing the seed ID- we want to change the bundle ID to a GUID. I know that the app bundle ID is used:

1. During installation to check that the distribution profile app ID (Second part) matches the bundle ID in the info.plist. So we have to generate a new provisioning profile.

2. By iTunes to segregate apps and identify upgrades for apps. I guess this means this will come out with iTunes treating it as a new app?

Are there any limitations you foresee with making it alphanumeric? Are there any other changes we will have to make?

This SO question states t开发者_StackOverflowhat it need not be in reverse domain name convention... can anyone think of why a GUID would be a problem?

Thanks in advance

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When you say APP ID, you are really meaning Bundle Identifier. App ID in context of an iPhone app means the App Store ID (ex: 29184024). You are not allowed to change the bundle id of an existing app per Apple, so you will have to create a new app from scratch. There are no limitations in making it alphanumeric, but if you create a new Bundle Identifier altogether, your older customers will not get updates.