Setting up and managing device configurations using Intune
@James Chan_110,Thanks for posting in Q&A.
From your description, I know you want to set up a policy for Android, iOS and macOS devices so that users can only download apps from the company portal and not any apps from the Internet.
Based on my research, I found that there are no related features in Intune and Android/IOS/macOS MDM.
Therefore, we suggest that you submit your feedback to Android, IOS and macOS MDM to get more improvement.
Thanks for your kind understanding.
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