If you have free data allowances on your iPhone plan or on your Internet Service Provider, curbi for Apple will stop these from working.
curbi for Apple works by securely sending all data from a managed device directly to the curbi servers. This means that all traffic from the device looks like it is going to curbi, not its final destination (like Facebook or YouTube).
Because of this, your ISP or Telco cannot tell that some of that traffic might be for its 'free zone' and shouldn't be charged for.
Please keep this detail in mind when considering large file downloads on a curbi-managed iPhone.
curbi for Android works by making filtering decisions locally on the device, so traffic can be filtered before it leaves the device.
This means that curbi for Android will have no impact on any 'free zone' data allowances that may be in place for a mobile device.