Hi!
I've discovered TIC-80 a few weeks ago and I'm having a blast with it :).
As with any virtual console, the ultimate dream would be to be able to play it on an actual console or something like that. I've tried the Android version, and it's very cool to be able to play your own games "on the go.". However, I think there is an issue with the virtual buttons placement. In portrait mode, the game display goes on top and the virtual buttons go on the lowest part of the mobile screen, which is perfect.
However, when playing in landscape mode, the display screen in vertically centered, and the virtual button are placed over the display screen, also vertically centered. I think it would have been better to have the display screen centered on top of the screen, and the virtual buttons on the bottom of the screen instead (like in portrait mode). That way, when you have a mobile phone whose height is greater than TIC-80 display area height, you can see the full display and have the button not covering it. Also, It feels more natural to tap virtual buttons on the lower part of the screen instead of the middle of it IMHO.
So I don't know if there is a technical reason in the difference between the way portrait / landscape mode are vertically centered on mobile, but in my opinion it would work best if both orientation would use the "vertical centering" way of the portrait mode.