Is it possible to export Android OS data to iOS?
Apple has an app in the Google Play store and a support article describing the required steps in details.

There's a nice page for switchers as well - https://www.apple.com/switch/ the one thing to pay attention to if you don't appreciate the marketing is the help from a live person through @AppleSupport and the Support App you can download on iOS once you've got your phone running. Try to transfer all the data within a day of getting your phone so you don't have two sets of photos and documents if you start making some on iPhone before you get everything over from the old phone.