Facebook might depend on the internet, but the social network knows that people don't always have good internet connections. You may be knocked offline in a subway tunnel, or live in a part of the world where fast internet access is rare. The company should soon have your back, though. It's testing a mobile News Feed update that sees which stories are already on your phone, and shows the ones you haven't seen based on relevance. On top of that, the test will periodically grab new stories while you have a good connection -- ideally, you'll always have something fresh to read.