Roblox has recently fixed the keyboard detection, but the mouse is still not functional like on desktop. You can‘t scroll with the wheel thing (I don‘t know what it‘s called, sorry!), you need to click and drag like with a finger. You can‘t zoom in|out the camera either. You can rotate it, but the UI joystick shows up as if you were using a finger.
It happens 100% of the time, in every experience. To reproduce, simply connect a mouse and a keyboard to an iOS device and join any experience.
Expected behavior
ScrollingFrames scrolling down|up when using the scroll wheel in an UI
Camera zooming in/out when not in an UI
The buttons not appearing when you rotate the camera.