Edgepad

Your phone as a control surface for your Windows laptop, over Bluetooth.

Edgepad is two programs that talk to each other: an Android app you touch, and a small tray app on the laptop that carries out what the phone asks for. No account, no cloud, no Wi-Fi: the phone and the laptop are paired once in Bluetooth settings, and after that the phone reaches the laptop directly.

What it does Corner rulers. Each corner of the phone holds a dial drawn as a ruler that wraps the bend. Slide along it, clockwise to raise. Volume, brightness, media scrub, zoom, app switcher or microphone level; Settings picks what each corner does, how long the rulers are and how tall. Trackpad. Everything between the corners moves the laptop's pointer. One finger moves and clicks, two scroll and pinch, three and four fingers do whatever you assign them: desktops, task view, media, volume, app switcher, and more. Media. The track, the app playing it and where it is, with previous, play/pause and next. Drag the three pieces anywhere on the surface. Keyboard. Tap the keyboard button and type on the laptop with the phone's own keyboard. Live state. The dials show the laptop's real volume, mute, brightness and playback position, and follow changes made on the laptop itself. Black on white or white on black, portrait or landscape.