ItcheSrulik,
Yes, airplane mode, flight mode, or whatever a particular manufacturer calls it, shuts off all connection to the network while keeping the phone on. It’s also useful to preserve battery life when out of range. Many dumbphones ( I like that term) have this feature as well.
Charlie,
I will be dan l’kaf z’chus that you use the tefillos in your Blackberry when a siddur is unavailable. (Not that it’s a terrible aveira otherwise, I’m being a bit dramatic, but I agree to the posters who opined that it’s not as good as using a siddur, because of v’hiyisem n’kiyim.)