Citrine on android literally took me 10 min to set up. There is also a simple privet server (no code gargin) with umbrel unfortunately you have to pay $500 for hardwar though umbrel is like a new ios device from what I could tell. You could set up a HAVEN relay (documentaion on how)

But if your looking to back uo your notes and broadcast simply go to https://backup.greenart7c3.com/ put in your npub (public key) the site will then back up all your infor to a .Json file and also broadcast to other relays automatically