Is there an official Apple Store App that lets me transfer my iPhone 4 data to iPhone 5S?

Recently got my iPhone 5S unlocked and I'm trying to transfer everything thats on my old iPhone 4 to iPhone 5S. I ask for an official Apple Store App because I want the transfer to be clean and secure and not have it leaked by one of those fake App Store apps. Basically i'm looking for a way to transfer an iPhone to iPhone.

You don't need an app, just connect to itunes and click backup, then connect new phone and load it.

Just back it up to icloud!

You don't need an app. Just back up the old phone, then restore the backup to the new phone. You can do this with either iTunes or iCloud. It's the standard way to move stuff from an old phone to a new phone.

You back up on iCloud or if you have a computer, back up the old phone to iTunes, then plug in the new phone to your computer and sync it

You use iTunes to do that.

Back up the 4
Restore from that back up on the 5s.