A book before bedtime can be a good way to unwind after a day spent staring at computer screens, but what if your tome of choice is on your smartphone or tablet? Won't the bright light mess with your sleep? Ebook subscription service Oyster certainly thinks so, and has released a new feature for its mobile apps named Lumin, which automatically adjusts your device's light levels based on the time of day. The result, they say, is better sleep and less eye strain — good news for habitual late-night readers. Read the full story from The Verge here.