I don't think that real-world conditions would be giving them 12 hours of recording throughout the day - a malicious app that explicitly asks people to swipe le

I don't think that real-world conditions would be giving them 12 hours of recording throughout the day - a malicious app that explicitly asks people to swipe left/right on pictures of kittens is a very realistic attack scenario and would know exactly when and where to look for the swipes.