Cache is temporary data apps keep for speed. When it corrupts, apps misbehave; when it bloats, storage vanishes. Clearing it is safe, you lose no accounts or files.
- 1Per app: Settings → Apps → (app) → Storage → Clear cache. Start with browsers and social apps, they hoard gigabytes.
- 2Find the hoarders: Settings → Storage → Apps, sorted by size.
- 3System cache partition (won't touch data): power off, boot Recovery (Power + Volume Up), 'Wipe cache partition'.
- 4Don't confuse 'Clear cache' with 'Clear data', data wipes logins and settings for that app.
Tip: There is no need for cleaner apps: Android manages cache automatically, and 'boosters' mostly show ads. Clear manually when a specific app misbehaves.