Mitsu Battery Angel is an aggressive system-tuning package that attempts to reduce background work by changing application operations, Doze behavior, logging, backup, connectivity, media, process scheduling, and storage maintenance settings.
A Broad Policy Bundle
Its scripts prioritize lower background activity by changing many unrelated Android subsystems at once.
Application Restrictions
The installer changes AppOps for every system package, including wake locks, background execution, account access, activity recognition, and foreground-service operations.
Forced Idle Policy
The boot script changes Doze constants, removes system packages from the idle whitelist, adds third-party packages, and immediately requests deep idle.
Reduced Diagnostics
Numerous log tags, DropBox records, tracing functions, crash services, tombstones, statistics services, and vendor diagnostic daemons are disabled or stopped.
System Changes Found in the Package
- Disables Android backup, silences the ringer, resets autofill, restricts content capture, and disables several service bindings.
- Changes Wi-Fi scanning and connection-selection options, toggles time-zone detection, and disables selected HDR types.
- Stops or suppresses system and vendor crash, statistics, tracing, logging, and packet-capture services.
- Modifies CPU control groups, cpusets, schedtune, block-I/O weights, and then lowers the CPU and I/O priority of processes owned by root.
- Runs filesystem trim operations, removes the Wi-Fi log directory, recreates it as an inaccessible file, and repeatedly clears logcat.
- Kills system packages and assigns restricted background and standby states after startup.
Likely Operational Impact
Because these policies are applied globally rather than from measured per-device profiles, lower background activity may come at the expense of delayed notifications, failed backups, silent calls, unavailable autofill, unreliable camera or media behavior, reduced Wi-Fi discovery, broken vendor services, or weaker crash diagnostics. The scripts do not provide benchmark evidence that battery life or performance improves on every device.
Several commands are vendor- or Android-version-specific. Unsupported commands may fail harmlessly, while recognized commands can change behavior far beyond CPU usage.
Risk and Recovery Plan
- Use a non-critical test device and record important global, secure, AppOps, backup, audio, display, and Wi-Fi settings before enabling the package.
- Keep a boot recovery method and a complete data backup outside the device.
- Verify calls, notifications, account synchronization, backups, camera, Wi-Fi, location, media, and crash collection after the first reboot.
- If behavior regresses, disable the module before attempting manual repair of individual settings.
- After uninstalling, review each affected subsystem. The uninstall script applies broad defaults and resets AppOps, but it does not preserve or restore every user's exact prior value.