The iPhones are :

  1. iPhone 2G
  2. iPhone 3G
  3. iPhone 3Gs
  4. iPhone 4
  5. iPhone 4s
  6. iPhone 5
  7. iPhone 5c
  8. iPhone 5s
  9. iPhone 6
  10. iPhone 6s
  11. iPhone SE 2016
  12. iPhone 7
  13. iPhone 8

And if it has a better battery life than them, how much better is it?