No, sorry. Airplane mode should stop all data exchange with mobile radio, but you should still be able to enable wifi and bluetooth while airplane mode is on.
I’m pretty sure all communication with carrier is disabled when airplane mode is on, which should save more power than disabling only mobile data transfer (in this case calls and messages still get transfered and connection with carrier is active).
Xmanager doesn’t compile the apk. I downloads the same files you have on telegram.
The main advantage of it over manually downloading the files is somewhat easier usage and update notifications.