Question: how to transfer all data from iphone 5s to iphone 8 plus?
Answer: On your new iPhone 8, Tap Restore from iTunes Backup, and connect iPhone 8 to iTunes, select a certain backup and restore it to iPhone 8. Simply wait for the restoring process finished, and a few steps to go to complete the update, then all data from old iPhone now is on the new iPhone 8. Enjoy your iPhone 8!