When we want to upload an App Release, we can change the App Signin Key, as per the image below
Similarly, in the App Signin tab, we can also upgrade App Signin Key (once a year).
What's the main difference between the two? What's the different impact on users?
p/s: I thought that changing the App Signin will affect external users and that they will need to reinstall the App. But the below warning seems only to apply to Internal and Close Track users.
Changing your App Signing Key essentially creating a new app. This means that users who have already installed your app will need to reinstall it in order to be able to use the new key. This will require users to uninstall and reinstall your app.
Upgrading your App Signing Key does not break compatibility with existing installations of the app. This is because the new key is used to sign new installs and app updates, while the old key is still used to sign updates for users who installed your app before the key upgrade. This means that users who have already installed your app will not need to do anything in order to be able to use the new key.
The main difference is that changing the key will break compatibility with existing installations of the app while upgrading the key will not.
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