> I promise I didn't have my expectations too high, I only had a few core principles

Proceeds to list 6 pretty high requirements.

The author’s not wrong, those are good requirements, but not to be expected from any standard app these days.

To dig on the first: “ Offline support”, this in itself requires a lot of work.

Going the technically easy way will often go in direct opposite to your business model (mobile ads or access info sales). Going for subscriptions or other mechanisms will have you do harder technical solutions, making that specific innocent requirement a decently high hurdle.