So why aren't we using e-paper screens in all of our electronic devices? For one thing, e-paper screens offer far fewer colors than LCDs and OLEDs. The Pebble Time can display only 64 colors, whereas LCDs can handle millions. E-paper's limited palette may be fine for text or simple animations, but it pales next to its competitors when it comes to photos or video. But color e-paper screens could prove attractive for budget smartphones, especially those sold in developing countries where long battery life and cheaper production are significant factors.