I think you should provide a daily data limit feature . In it device automatically stopped data when the daily limit is cross and also the limit will be adjustable..
Bro, I think you are talking about set data limit.. Go to settings>Connections>Click on data usage>now select billing cycle and data warning>here you can set data limit if your choice..
Bro, set your data as per your requirement, now it depends on your usage..and it's not monthly..billing cycle is monthly..data limit is solely depends on your usage....you can check it..
eg: if you set your data limit of 2gb and consumes within a day, then you can't use your data connection..so its totally upto you..
