It is played with a mouse and a keyboard — you aim with the mouse, shift timelines with a key, and read the room while paused. That is the game, so it is built for a desktop window rather than adapted down to a touchscreen.
Open it on a computer with a mouse and keyboard, in a window at least 820px wide, and it will play properly. A tablet will not work even in landscape — there is nothing to aim with.
The idea, in one line: every time you rewind, your previous attempt stays in the room and repeats everything you just did.