in terms of battery life for the iphone 5, which battery is better? 3.8v1440mAh or 3.8v1560mAh?
The battery life of your iPhone depends on it's usage. 1440mAH or 1560mAH refers to the basic term that if your phone uses 1mA per hour(i.e 1 W/v) it can last for 1440 hours. But the usage will depend on what all software you are using. Like mobile network and heavy graphic intense games will use more power, applications that don't require a lot of processor power to work,(such as a clock) will not take so much amount thus you will have a longer battery life.

There are various articles explaining this online, if I find a suitable one I will post it in an edit soon.