> Possibly charging app developers directly for access to the app store. This is already the case. $100/year USD to get the privilege of being on the App Store

> Possibly charging app developers directly for access to the app store. This is already the case. $100/year USD to get the privilege of being on the App Store. Actually, getting on the App Store is not even guaranteed after you pay the fee, since you still need to pass their review process.