The battery icon in the top right corner of iPhone shows how much battery you have but it is not a clear enough indicator. Displaying the battery percentage on your iPhone is the only way to know how much battery is exactly left in your mobile phone.
Turning on the battery percentage adds a numerical display of your iPhone battery life. Having the percentage display gives precise indication of how long your iPhone will run before need to recharge it.
iPhone does not come with the battery percentage display enabled. To get the battery percentage on your iPhone follow the below given steps. This will work on iPhone 3GS, iPhone 4, iPhone 4S, and iPhone 5.
How To Display Battery Percentage On iPhone
1. Tap Setting icon
2. Open General.
3. Tap Usage.
4. Scroll down and find Battery Usage.
5. Turn On Battery Percentage to show battery percentage in your iPhone.
You will now have a numerical percentage representation of your iPhone battery life along with the generic battery display symbol to the top right corner of the screen.