The amount of data transferred depends on the device types (the size of the hostOS varies somewhat between the versions)
- the resinOS image is between 70-120MB
- the supervisor is 40-70MB (though some updates downoad less, as docker layers between versions are cached, and newer versions are on the smaller end)
- the 1.x->1.x updater tool is ~50MB (only downloaded for those updates)
We are working on reducing this constantly. For example with the release of balena we’ll be able to use delta updates for the host OS and the supervisor updates too, which should be better under all circumstances than the current base level.
Also, this other topic might be relevant to your interests, if you haven’t seen it yet: Updated bandwidth usage numbers