But actually this is unlikely to make a big difference on battery drain. Pokemon GO appears to be built on Unity and Unity is pretty notorious for having poor battery management. Whether you're pegging CPU or not, Unity burns lots of power. So, the incremental battery life hit is likely to be low in doing image processing on top of a frame.
Seriously, fuck Unity. It's the indy game equivalent of vendor-lock in, with everything negative about it.
They can't be arsed to fix a simple VSync bug on Linux, meaning even simple sprite games, or even more insulting: TIS-100, a game about optimising assembly on fake retro-hardware, deliberately made to look like a terminal, always burns 25% CPU power on my laptop.
More importantly, as Paolo Pedercini[0] mentioned on Twitter recently:
> I can open my Flash crap from 15 years ago no problem, but a project I made last year in Unity 5.1 crashes silently if rebuilt in Unity 5.3 I'm telling you: today's indie game production is a Unity monoculture that will disappear at the next hardware architecture cycle