Turning off cellular completely

Sometimes you just don't need a cellular connection. Knave been experimenting with Google Voice over 3G or Wifi as my phone connection. When I am at home I just don't need the cellular connection going all the time. I figured out how to turn it off completely. It is really quite easy.
1. Put your phone into Airplane Mode. On Android this is in the Network Settings. iOS puts this first in the main settings list.
2. Turn on Wifi, Bluetooth, or what ever else you want.
DONE!

This works because Airplane Mode disables ALL network transmissions, effectively cutting the phone off from the outside world. However you can selectively turn different radios back on. Wifi, 4G, Bluetooth, and NFC are usually the ones you have control over. So, next time you are on that flight and don't want to run your battery down unnecessarily, try this trick!