When you want to try your program on your Lego Mindstorms robot, you need to download it onto the EV3 brick. This works fine with the USB cable or Bluetooth (I tried it with an iPad). However, if you want to use Wifi you will need a Wifi dongle, since this part of the electronics is not included in the EV3 brick. There is not much to find on the Lego website about this and apparently there is only one very big dongle that is officially compatible with Lego.
Here the link to a website that offers an alternative. I have not tried it yet, will try this week and will post an update when I know if it works…
thetechnicgear.com/2014/04/howto-configure-wifi-edimax-ew-7811un-mindstorms-ev3/