eyeFI has evolved into a great way to WIFI-enable any SD-using camera (which are most of them).
The WIFI-enabled SD card lets you take pictures and instantly transfer them to your phone, tablet or PC.
Unfortunately the device needs an app on the other end, and they do not have one at present for Windows Phone.
Fortunately it seems one is on the way with eyeFi support saying:
Thank you for contacting our Eyefi support center.
I would like to inform that it is not known when the app for the windows phone will be released.
At this moment we are working on it, but there is no possibility that I can tell you when it will be released.
Jan van XXX
Eyefi Support EU.
While we would not hold our breath, it is good to know that even these niche utility apps are on their way.
Thanks Sarkis for the tip.