I got this in a previous Woot, after months of being almost but not quite tempted enough to get it at the $50 list price. It's phenomenally versatile; you can mix and match buttons from different devices on the same screen. There are also "drawers" that slide out when you press a button. The app is free, so you can noodle around with designing a remote before buying the hardware.
L5 has another app, FreezeFrame, that uses the dongle as a camera remote. I have an old first-gen iPhone that I use as an iPod Touch (no cell service); I can set up my SLR, set that in front of it, and shoot time lapses. The only feature I'd like to see added is a mini or micro USB so that your device can be connected to power while the dongle is connected.