About 2.5 years ago I left behind Android and went to the Dark Side. Bought an iPhone. It was frustrating to use at first because changing OS is a pain in the ass, but I got used to it and actually really like it now.
But I still have two big complaints:
There ought to be some kind of icon in the toolbar to show me I have unread notifications. I miss this very much from Android, which would show icons for the apps that have notifications. The Apple Watch solves this by having a notification icon, but I shouldn’t need to buy a separate device for that functionality.
I cannot stand that I can only go back by swiping from the left side of the screen. On Android the swipe in gesture from either left or right side could be set up to be the “back” action. I understand why this is, Android developed with a dedicated back button and thus has an OS-level back command, whereas iOS is highly contextual and you flow through apps and menus differently than Android, and it has no dedicated universal “back,” so swiping in from the left is back and swiping in from the right is forward. It makes using a large screen one-handed unnecessarily difficult.