With all the different resolutions for the phones now these days.
What resolution do you use?
I am using 1000 x 1750 for the longest time, but wondering about that now.
I use 568x320 for most of my my retro games.
but especially annoying when you have to deal with the black notch aswell. & are even all the iPads 16x9 ratio? get those black bars rolling
True 16:9 Resolutions
Modern monitors and tv's use 16:9 widescreen output. Using a smaller 16:9 output size like 640×360 or 1024×576 will have you be able to play your game in fullscreen with no lose in resolution.
1920×1080 all the way
I use 1280x720 for my desktop apps every time, and I also be sure to set them to scale to the screen they're on without changing the resolution. Basically, I set the application to maximize at start with no headers or menus so it can "go full-screen" without changing the desktop resolution
I only make mobile games and typically have "Fit inside and adjust window size" enabled and have a 1536x3000 frame to fit any screen (and make it easier to port my game to iOS after making it for Android initially). Then I use the Window Control object to get the width/height of the application window and use that to position everything dynamically (for things like HUDs I find it very useful). Above all I make all my graphics 1080p so they look sharp on any screen. I haven't found any performance issues so far.
While the solution i posted works, it's not perfect by any means since your objects don't scale up with the screen size so you may end up with everything looking quite tiny. I've started using a different method which scales up properly and also adjusts the frame size. Problem with that is that the "base" resolution is locked i.e. if I set my application window size to 1080x1920 and ran my app on a 1080x2160 or 1440x3040 display everything will look nice and scale properly and dynamically adjust things like aspect ratio so no more black bars, but if I ran it on a 720x1280 screen it would be sort of cropped in and your objects won't scale down properly. TBH in 2019 very few people would have a resolution lower than 1080p but it's still a considerable chunk nonetheless. I've attached an MFA with my settings copied over so you can have a look for yourself.
If anyone has a better way to do this I'm open to seeing it!