I don't really use too many apps overall. Most of my bugs are in the core OS itself and Safari.
For example, I get hit with this one pretty often (blank page in Safari): https://discussions.apple.com/thread/250740002,
Going to reader view and back sometimes fixes it. Force quitting Safari always fixes it.
Fairly often Safari will stop accepting input. Force quitting fixes it. Also often after a pinch zoom, it snaps right back to 100%. This happens on Reddit and HN very often.
Airdrop works maybe ... 5% of the time? Just now I tried to airdrop an image to my wife. My phone said "waiting...", and nothing happened on her phone at all. Tried several times. Nothing. Airdropping to a Mac I think I've gotten to work once or twice.
I get keyboard rotation issues often, like this: https://twitter.com/mattegreer/status/1205698892555120640 (that is my tweet).
I email myself URLs from Safari. But about half the time I have to email myself, wait a few seconds, go into Mail's outbox, and then send the email from there. Otherwise it will just sit in the outbox indefinitely. This is actually true of all emails, but I use the Gmail app now for normal emailing. Added fun, sometimes the outbox doesn't show up until you force quit Mail.
Lots of annoying lack of polish issues. For example, expand an image in messages to be full screen, then return to the thread. Often you get a blank screen, because it has scrolled itself down beyond the messages by about a screen's worth. Sure, just scroll back up to fix it, but I expect a better experience from such an expensive phone.
My previous address (I just moved a week ago) has not been added to Apple maps despite the complex existing for about 2 years now. When you enter the address you get a different address about 10 miles away. Sure, not a bug but a data issue, but all the same from the user's perspective. This caused all kinds of pain. So many people use Apple Maps because they just use the maps app that came with their phone. I got situations like this, https://i.imgur.com/v13VYZM.png, all the time. Package deliveries, appointments at my house, you name it, it was such a mess. I contacted Apple support, they assigned me a support representative. Over Facetime I showed him my address not being in Apple maps and how it is in Google maps. After 2 phone calls with him and many emails, I finally just gave up and accepted it.
These are the ones I can think of quickly. I've also had tons of issues with carplay and many, many third party apps. But it's hard to know who is to blame for these issues.
Over on Android, the only real issue I've encountered is part of the phone understands I have work and personal profiles, and other parts think I don't have a work profile and want me to set one up. Admittedly, this is a pretty annoying bug that does cause some headaches, but it's really the only thing I've hit. Chrome, Gmail, pretty much everything else has been just fine for me.
