A new feature called Instant Videos that downloads and caches Facebook videos to your phone while you’re on Wi-Fi so you can watch them later on the go for free. Users will see lightning bolt icons on pre-loaded videos. The feature could also benefit Facebook’s new Watch tab of original video content, allowing it to cache episodes so people could watch them on a train or elsewhere that they might not have a strong connection or want to use up their data plan watching longer-form videos.