Just saying, if you are careless enough with your phone to drop it all the time, you may not deserve nor need a phone. And the iPhone 4S and below have glass backs so yes, they shatter easily. However, the 5 has a strong metal back and the 5S has an even strong metal backing. They are especially more drop proof than the plastic backed Androids.
Accourding to latintimes.com ::
And the 4S ::