10000mah and an ARM A53 mean it should last 10 hours or more with moderate brightness settings. It's hard to beat this for a light cheap terminal/browser with plenty of battery if that is something you need.
I bet it's software compositing. GPU acceleration doesn't work on those boards last time I checked, so it's probably having to do a lot more work on the CPU. It would also explain why it feels so sluggish despite being on paper more powerful than a Raspberry Pi. You should probably forget about trying to play video on it.
