If you're going focus mobile app, web is just nice to have, I would suggest use native (Swift/Kotlin,Java) to build your app, it may take some time at the beginning, but it'd save a lot of your time on dealing verity of issues (like setup Payment, Notification)。
I'm building a blogging, journal app (https://giki.app) and it's using React native, it got up and running very quickly at beginning util I need enable in app purchase.