Your old phone sits, languishing, in a drawer, ignored on a bookshelf; perhaps it's propping open a door. It doesn't have to be this way. You have plenty of ways to reuse your old smartphone. Sure, you could sell your old smartphone, but why bother when there are so many ways for you to reuse it? Here are 10 ways you can make your old smartphone useful again. 1. Your Old Phone Is a VR Headset! No,