【New Technology Application】NFC technology is used to transmit display content to the ink screen of the mobile phone case with low power consumption.【Easy to DIY Your Personalized Phone Case】exciting feature is that this case allows you to upload your own mobile phone pictures. With just a few simple steps, you can easily personalize your case by selecting your favorite pictures or designs. 【APP is Easy to Use】Search the APP "Ai Phone Case/CASECONN", download it to your mobile phone, open the APP, and you can freely edit and transfer pictures and text.NOTE: The ink screen we use is a black, white, red and yellow four-colors screen, it can display simple black and white pictures better.