The battery is 2Ah because I have it lying around (aka free) and because I'm extremely limited on space. 2Ah should be sufficient as the main RGB LED, Arduino and screen shouldn't draw more than 300mA. The MintyBoost circuit will provide 500mA, so this should have a runtime of at least 2 hours.
I'll add WiFi/Bluetooth in a future release? WiFi-enabled LED torch?