Floating windows
Popups, sheets and dropdowns all use this one.
Telling the player something
Floats at one side with no scrim.
HUD
Polish the big panels all you like — what catches the eye is always something small: a word split in two, a glow chopped off, a…
Waiting, telling, counting
Sits at the bottom (or the top), above the safe area and the keyboard, and leaves on its own.
Forms and lists
One line at the top of a five-field form saying "check your input" does not say which field.
Shapes games actually use
Familiar web shapes, rebuilt around what a game needs from them.
Over the screen
GoSheet comes from the bottom, which is right for a phone held upright.
GoStyle — one place things are made
Call Button.new() directly and padding, height and wrapping drift slightly from screen to screen.