Everyone knows all the apps on your phone

I still, will never understand the need for native "Apps". To this day, I have never seen an "App" that couldn't simply have been a website/webapp. Most of them would likely be improved by being a webapp.

The only benefits I can see of "Apps", are the developer get's access to private information they really don't need.

Yeah, they get to be on the "App Store". But the "App Store" is a totally unnecessary concept introduced by Apple/Google so they could scrape a huge percentage in sales.

Web browsers have good (not perfect) sandboxing, costs no fees to "submit" and are accessible to everyone on every phone.

For me, there are a lot of applications that I want to be able to load regardless of whether I have a connection to the Internet or not: calendar, notes, mail etc. They can sync/send/whatever whenever I am next online.

Ah yeah. While this is mostly implemented terrible, a web app can absolutely do this for you using service workers. So you can install a webapp to your homescreen and use it without an internet connection at all.