I just did a quick search.
http://support.apple.com/en-us/HT205063
http://www.lifewire.com/transfer-data-from-android-to-iphone-5220470
There were many hits when I searched. The title on one said "8 ways...." but you should only need one.
Apple supplies an app (first link)
The second link appears easier to read, imo.
It says you should start with a NEW iPhone. If you have already set up your phone it requires you wipe the iPhone and start over. Again, I wouldn't expect this to be your problem: take the phone to any dealership which sells iPhones and I'd expect them to take care of all.