Not happy that iOS 9's WiFi Assist feature is quietly gobbling your iPhone's cellular data for the sake of boosting your WiFi performance? You're not alone -- and you might get compensation for your troubles. A California-based couple has filed a class action lawsuit accusing Apple of doing too little to warn iPhone owners about WiFi Assist's data use. Allegedly, the guide it posted in response to concerns about the feature doesn't cut the mustard. It "downplays" the kind of overage charges you could rack up after upgrading to the newer iOS revision, according to the complaint.