Random restarts have two families of causes: software (an app, a bad update) and hardware (battery, overheating). Safe Mode is the quickest way to tell which one you have.
- 1Boot into Safe Mode. Stable there? An installed app is the cause, remove recent ones.
- 2Check for overheating: restarts during games/charging point to heat, remove the case, avoid charging while gaming.
- 3Update Android and all apps.
- 4Check battery health, a worn battery causes sudden shutdowns that look like restarts.
- 5Wipe the cache partition from Recovery.
- 6Persisting? Back up and factory reset; if even that fails, it's hardware (battery or board).
Tip: Estimate battery wear with our calculator, below 80% health, unexpected shutdowns become common.