Good question. I recently answered this:

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The big difference is that once developers start signing their own apps, and using different relays (we're a few months away from that), there effectively is no centralized walled garden. No other app store doing that. Does that help? 

 If I understand you correctly none of what you mentioned has been implemented yet but is planned for the future. If yes, then this clarifies a lot and explains why zap.store looks like an ordinary appstore to me at the moment. 

 Correct. Some people find it is a better UX than Obtainium, or manually downloading APKs