More and more people are buying smartphones than ever before, but iPhone 4S users especially are seeing how important it is to have the best battery life. Really the only way to compare which devices have the best battery life is by comparing how much talk time each one gets. In other words, there is really no way to compare devices' battery lives when it comes to Web browsing or listening to music. There are simply too many variables to measure with different screen sizes, operating systems and microchips all giving different devices different battery life depending on what you are doing with it.

Until such a test can be developed, the only way to compare these devices is by looking at talk time. If you don't use your phone for talking as much, you can still get a decent idea of which devices (or manufacturers) do the best.

iPhone 4S, despite having some battery problems that have popped up, does get good battery life. An apparent iOS bug has been biting some, but not all, iPhone 4S users, and causing rapid battery drainage. Remember, if you are having to charge your phone every four hours, take a minute to see what you are doing with it. With heavy use, frequent charging is going to be a way of life with most high-end smartphones until battery technology evolves a bit more. iPhone 4S It doesn't make the top five list, but it would be in the top ten. Start the slideshow to see the five best phones with great battery life. Tell us in the comments if you've ever replaced a smartphone battery or if you miss your feature phone because it went three days between charges.

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