The iPhone 6
The IPhone 6 is a lot thinner than the 5s and 5c. You can add voice, video and location to any message. For the first time in apple history the home screen can be horizontal. The keyboard knows what you are going to say. It may sound creepy but it’s not, it only means that when you are trying to type and you did it wrong, your phone will know and correct it for you.
The iPhone 6 and the plus are both bigger than the 5s and the 5c. The phone had equal or bigger battery life on every metric than the 5s. The camera on this phone is way better and can take a great photo even when you are shaking the camera. It can be good for people who have shaky hands.