There are so many freakin' phone apps there it makes my head spin. That said, which one(s) do you find the most helpful, productive, and/or fun to use? I love Night Sky (iPhone only. There are other similar apps for android users) https://apps.apple.com/us/app/night-sky/id475772902 My wife loves Vivino. LOL https://play.google.com/store/apps/details?id=vivino.web.app&hl=en_US What say you?
For some silly reason, I like to watch the ISS flyovers. This app keeps me informed of those. When we were in Moab, and took that sunset jeep ride to the top of one of those amazing rocks, my wife and I were able to witness an absolutely incredible array of stars, the Milky Way, etc., etc., etc.! Reducing/eliminating light pollution is da bomb!!