Quip is an odd new app that looks like it could be incredibly useful. It’s billed as a word processor, but it combines text editing with instant messaging, change tracking and sharing — plus it has a very cool interface.

Oh, and it works on your iPhone, your iPad and your Mac (in the browser).

Kicking off this week’s must-have apps roundup is a beautifully simple timer app for the iPhone that could mean you never need to set timers manually again. There’s also a terrific app for beaming your photographs to almost any display — without additional hardware or software. Plus lots more.