With this particular update, the software version will be bumped up to 01061.00074.14391.37104, which can be rather tricky when you are trying to compare it with your Nokia Lumia 635’s existing software version number. For those who have made use of T-Mobile’s free inflight texting before, this is an update that is well worth looking into, but otherwise, you will not miss much if you don’t even fly in the first place.
Just in case you are not too sure on how to check your handset’s existing software version, just perform the following steps and you’re good to go. Swipe left to Applications from the Home screen, tap on Settings, then About, and More Info. Check out the Firmware revision number on the smartphone from there to figure out whether you would need to update or not.