I'm a light data user. I track my usage carefully, charting my booster usage monthly and checking which apps were drawing data via my iPhone's settings (resetting statistics each month). Last month I used 128MB but 64MB of that was for "DNS Services" (under "System Services").
I can find all kinds of things to try tinkering with when I google the issue but I didn't know if Koodo had some specific tips: if there's a recommended DNS server or search domain, or a way to confirm I have the correct carrier settings now, or refresh them or something.
iPhone 5 running 10.3.2