I have Nikon D750 and never used Wi-Fi with it before reading your post. Decided to try it and now I know how to use it. You need to install Nikon Wireless Mobile Utility. You can reed this article http://www.nikonusa.com/en/learn-and-explore/a/tips-and-techniques/using-your-nikon-cameras-built-in-wi-fi.html and find there link how to find it and install for free. After that you should connect your phone and you camera to Wi-Fi. On your phone screen you will have window Nikon WMU. Click on this window and you have choice Take photos /with your camera/ or View photos. Good luck.