A phone already takes up a valuable pocket. XTEINKs answer to carrying an e-reader is to put one on the back of it. The XTEINK X3 is a 58-gram E Ink reader that attaches to compatible magnetic phone setups, giving.. The post A 58-gram eReader that snaps onto your phone: XTEINK X3 hits $55 for Black Friday early access appeared first on Gadget Flow.