Sabbir Ahmed 
After a system update, a few days of heavy drain are normal and a few weeks are not. This shows you how to read the battery screen properly, find the app that is actually responsible, and fix it.
“Unfortunately, App has stopped” is Android telling you the app died, not that your phone is broken. Here is how to narrow the cause down in a few minutes and fix it without wiping anything.
An app that refuses to update is not one problem — it is about seven, and they have different fixes. This walks through them in order, and explains the one case where reinstalling really is the only answer.
Everything else in the house is online, but your phone insists the Wi-Fi has no internet. Android is running a specific test behind that message — and once you know what the test is, the fix is usually one setting away.
The Play Store says “Download pending” and nothing happens. The message is not an error — it is a queue. Here is how to find out what is holding the queue up, and nine fixes in the order worth trying them.
“Unfortunately, the app has stopped.” You reopen it, it dies again, and the only advice anyone gives is to clear the app’s data — which throws away your chats, your saved game, or your login. Clearing data almost always works. It is also the last thing you should try, not the first. Here is the … Read more
WhatsApp says it is backing up, the progress bar sits at 0%, and an hour later nothing has happened. Or the backup screen says “Last backup: never” on a phone you have used for two years. This is almost never one big fault. It is one of seven small ones, and they are worth checking … Read more
You go to install an app, the phone says “Insufficient storage available”, and then you check and there are four gigabytes free. The message looks like a bug. It usually is not. Android is not counting the space the app will take. It is counting the space it needs while installing — and that is … Read more