Hot answers tagged battery
Never let it run down below 10% if you can help it. Running down to "absolute zero" harms your battery (and might even render it inoperable – which is why most devices shut-down before reaching that point). Modern LiIo batteries don't suffer from "memory effect", so ideally you'd plug-in a charger whenever possible: "trickle-charging" doesn't hurt them, low ...
Android is automatically keeping Wi-Fi on while the phone is sleeping (Keep Wi-Fi on during sleep) and always scans for available networks (Scanning always available). They must be keeping it on. Try disabling them from Settings > Wi-Fi > Advanced.
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