Smartphones (© iStock)Smartphones; you probably have one in your pocket right now - that is if you're not reading this on your mobile. Even if you have just invested in the best phone around it's likely that within only a few months there will be a new iPhone out, the latest Sony to boast an incredible camera or the next iteration of the wildly popular Samsung Galaxy series. Long gone are the days when mobile phones were just for making calls. Now they are app-running, selfie-shooting, music-playing powerhouses in your pocket.

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