Excess data usage on my Galaxy S5

In the last couple of days Gospel Library has eaten up 1.3GB of my 2GB monthly allowance. What could have happened and how can I avoid this in the future? I used GL yesterday listening to 1 session of conference but I frequently listen to conference. Could using the text to speech feature on some manuals eat up data? Any hints? Thanks.

I can't make any suggestions other than that you tell your device to only use wifi, not your data plan (at least as a norm, and enable use of the data plan as an exception - manually, when you don't want to wait for wifi).

This option is in Settings > Advanced Options > Allow mobile network use (at least, that's where it is for me.

FWIW,

Liz

You can download the audio while you are on wifi, so you will have it handy to listen to while you are out and about.