said by Biggles :2. Some web sites probe their user's connection speed. If they "think" you have a high speed connection, they serve you higher resolution graphics and more of them than they would otherwise, which can result in significantly higher usage numbers.
This is the main reason your useage is up. For example: YouTube always selects the highest possible resolution based on your connection speed. You now have to manually "choose" a lower Resolution when watching any YouTube.
Any video you watch will "auto choose" the highest resolution based on your 4G download speed.
Also web pages that have Flash ads...the same thing. "Hi Res" adverts eating your data.
Install Flash Blocker to your browser. This let's you choose which Flash Vid you want to let pass.
Also install and Ad Blocker, so you won't be downloading Hi Res Ads.