By far the best feature for me is DUAL APPS: separate copy of an app that runs absolutely separated from the parent app. This way you can have e.g. two Slacks or two Facebooks or LinkedIns logged into two profiles without endless switching.
Other sweet things: support for WireGuard VPN, customizable keyboards (I'm a big fan of "finger slide" typing pioneered by, I think, Swipe), giant Google Calendar widget on the main screen...
That's another big issue: as a user in China, AppStore doesn't have a lot of apps, mainly VPNs and some other apps. On Android I can always just sideload or use APKPure or whatever. On iOS I have to jump through a lot of hoops to get a working VPN app in China.
Right. In a way, Android in 2019 feels like more forward, experiment-friendly environment. Some Android features get adopted into iOS later. It contradicts Apple's branding, but it is how it is. For Apple it's more about stability and privacy now.
Using this one right now: https://f-droid.org/en/packages/com.wireguard.android/ - but it could be better. Someday I'll flash a kernel with WG support (how about that, iOS? :) and it will be faster. Seen the difference on another phone.
Other sweet things: support for WireGuard VPN, customizable keyboards (I'm a big fan of "finger slide" typing pioneered by, I think, Swipe), giant Google Calendar widget on the main screen...