Reqest: sync real pysical battery to emulated ds/dsi battery

[Littlemac123]

On newer builds on desktop melon DS there is controles to adgust how much battery you have, i bet it would be possible to just auto sync it to the phones battery levels. In games they would sometimes warn you when your battery was low, like in sonic colors the game land planet in the planet select screen flashed green on good battery and red on low battery.