I connected my phone via hotspot to my laptop and browsed ikeja electric site for about 20mins and when i checked my balance i had used up 543mb...isn't that crazy, no videos, no media just reading thru the sites menu.

These rip offs from these mobile providers is getting out of hand. One dumb customer care agent had the dumbness to tell me its because i was using 4g and tethered my phone. Haba! 543 mb just going thru a site without opening any media? Smhh

Your browser might be the culprit. I used to experience same until i installed Datally and found out ucbrowser was using almost 400 mb for housekeeping everyday. I uninstalled it and now use ucmini instead: problem solved