1: Exempt the app, then tune inside it
Do not fight the emulator with system battery saver: exempt the Delta Emulator Android app so it runs properly, then save power with the in-app settings below. A throttled emulator stutters; a tuned one sips.
2: Drop brightness to 60 percent
Pixel-art games were drawn for dim CRTs; they look correct, not dark, at moderate brightness. This is the biggest single saving most players ignore.
3: Cap the frame rate honestly
If the emulator offers frame limiting, match the original system's rate rather than your screen's 120 Hz. Rendering 120 frames of a 60 fps game wastes power for zero benefit.
4: Kill the heavy filters
CRT shaders cost GPU power on top of CPU power. Use plain integer scaling on the go; save the pretty filters for plugged-in sessions. The lag guide explains the same trade-off from the speed side.
5: Airplane mode for offline play
Your game files are local, so the radio can sleep. Airplane mode (or at least disabling mobile data) cuts a surprising amount of drain during long sessions. Note this also pauses the ad network, which is a side benefit, not a recommendation to block ads permanently.
6: Play plugged in for marathons
For sessions over an hour, just plug in. Heat is the real enemy: a hot phone throttles, and a throttled phone stutters. A cool phone on a charger beats a hot phone on battery every time. The build these numbers came from is the current 51 MB XAPK.
