WhatsApp for Xiaomi Mi 5s Plus

MIUI's aggressive background sync and location services are usually the culprit. Go to Settings > Battery & performance > App battery saver (or Choose apps) and set heavy apps like Facebook and WhatsApp to 'Restrict background activity', leaving 'No restrictions' only for apps you actually need running in the background. Also reduce location aggressiveness under Settings > Location by setting permissions for individual apps to 'While using the app', and clear any rogue apps holding wakelocks. After a reboot, standby drain should drop noticeably. See how others solved this on Reddit

Xiaomi hardware generally holds up well for several years, but the Mi 5s Plus is well past its official update window, so the main risk is a degraded battery and an outdated MIUI/Android version rather than the phone failing outright. Keep it healthy by avoiding heat while charging, backing up and doing an occasional factory reset (Settings > About phone > Factory reset / Erase all data) to clear accumulated bloat, and consider a battery replacement if you notice sudden shutdowns. With those steps it can remain a solid daily or backup device. See how others solved this on Reddit

Most system ads come from MIUI's ad service, so open Settings > Passwords & security > Authorization & revocation and disable 'msa'. Then open each stock app (Security, Cleaner, Downloads, File Manager) and turn off 'Receive recommendations' in its individual settings. You can also disable system-wide recommendation content in Settings, and uninstall or disable many preinstalled apps via a long-press on the app icon if your build allows it. See how others solved this on Reddit

The Mi 5s Plus was sold mainly as a Chinese-market model, so its LTE band support is geared toward Asia and may miss bands like Band 20 (800MHz) used by many European carriers, which can mean weaker rural coverage. Before relying on it, check the supported bands (dialing *#*#4636#*#* opens the testing menu on most Android builds) and compare them against your carrier's frequencies. If a key band is missing you'll still get calls and texts, but expect reduced data reach in some areas. See how others solved this on Reddit

For everyday tasks like messaging, browsing, and media the Snapdragon 821 and generous RAM still hold up fine, but you're stuck on an old Android security patch level and won't get HyperOS or many modern app updates. If battery life and performance are still acceptable, keep it; if you're hitting app incompatibilities or constant slowdowns, a newer Poco or Redmi model is the natural step up. A clean factory reset first often makes it feel fast enough to delay an upgrade. See how others solved this on Reddit

MIUI accumulates cache and background services over time, so start in Settings > Apps > Manage apps to clear cache on heavy apps and disable autostart for ones you don't need (Settings > Apps > Permissions > Autostart). Reducing animations in Developer options (set Window, Transition, and Animator scales to 0.5x) and keeping plenty of free storage both help responsiveness. If lag persists, a periodic factory reset remains the most effective fix. See how others solved this on Reddit