Some time ago my iPhone 4 died, claiming it was low on battery. Strange, I thought, because it reported 15% just a few minute earlier. So why would my iPhone discharge before the battery is drained?

Turns out the iPhone 4 (or any other model, perhaps) can at times report an incorrect amount of charge. Perhaps you’ve never fully charged the device, or perhaps a bug occurred.

Anyway, how do you fix the battery meter on the iPhone 4?

  1. Restart your iPhone.
  2. Then, you drain the battery. Let the phone discharge on its own, or speed it up by using it (i.e. playing a game).
  3. Let it sit for an hour or two. This is to make sure it’s empty.
  4. Start charging your iPhone, and be sure not to interrupt the charging
  5. Let it sit for an additional hour or two after it’s fully charged. This is to make sure it’s fully charged.

That’s it! Now your iPhone should be recalibrated and report the correct charge.