Almost every mobile device is really limited by battery life - but there are some devices that stand out as being horrible and some are pretty fantastic. The interesting thing is that the devices with the best battery life are not usually high-end or expensive devices. They are mainstream or budge phones. There is a pretty comprehensive list of technology that makes battery life great - and it's not the fastest processors or the biggest screens - or even the biggest batteries for that matter.
Another one of the factors defining the battery life of a device relates to the screen. There are a few variables at play here: the screen size matters, so does the resolution, and the screen type as well. Along with the screen tech and the spectrum of brightness of the device, these factors influence how quickly the battery drains.