Learn How to Examine Your iPhones Battery Usage
A common question we hear is, "Why is my iPhone/iPad battery draining so fast?" Luckily, Apple provides tools that help you see exactly how your iPhone uses its battery over the last 24 hours and---with less detail---over each of the last 10 days. Plus, you can tweak settings that will improve battery life, both in the here-and-now and for as long as you have your iPhone. To access these tools, go to Settings \> Battery.