I've been using the app. Some said they got charged, but it hasn't happened to me so far.
Don't forget to disable the auto-renewal if you don't want it to happen the following month. Can disable almost immediately after the activation, as the remaining from the 500MB will still be valid for a month.
I don't have the USSD nor SMS code offhand. Will post if I do later.
Thanks for coming to my rescue again, bro.
U wake up early, bro, or u didn't sleep last night ? Browsing HWZ at 5am