Here's a screen shot from a recent Thursday night digital radio net that might help give you an idea of what it is all about if you haven't tried it.
The screen shot shows a received radiogram form as it would look on paper displayed on an Android tablet or phone.
Note: The only equipment used to receive this was an handheld radio (HT) and an Android Tablet.
No cable, or interface, was used between the tablet and the HT. The tablet's
microphone decoded the audio coming out of the HT's speaker.
The app on the tablet is AndFlMsg which is a free Android application that
implements a some parts of what's available in the FLdigi suites.
While in this case, the information for the form could have been relayed by voice, it could have easily been a picture, spreadsheet, or other file that would be difficult or impossible to relay by voice if the only available infrastructure was a radio.