15 things you didn't know your iPhone could do

The iPhone's iOS interface is simple and intuitive to use, but there are also subtle features that require some time and effort to discover.

You might have, for instance, downloaded a scientific calculator app because you missed the in-built one. Also, your passcode doesn't have to be 1234 (not that we recommend it): it can be a mixture of numbers, letters and symbols.

Here are 15 nifty tricks to help you get the best out of the iPhone.