So I bought my smartphone on 16 Apr 2016, and only started using since 18 Apr , right now this is what my data usage looks like: Used 135 MB I am on Starhub 4G 3 plan (postpaid) which comes with 3GB of data, my friends told me 3 GB is more than enough, it is so true, I leave my data on 24/7, surf net, whatsapp, even watch videos, utilization is less than 5% lol, maybe should start using my phone as a hotspot at work since my workplace internet is shit, why let it go to waste ;) Same goes for my wife, she is also on the same plan, the highest she can hit in a month is 1GB, also wasted, now I tell her to just leave her data on, no need to off and on, she is afraid that she might overuse, she has the My Data Mgr app which will alert her when usage reach 90% so really no need to worry.