Hi.
Apparently there is no WP8.1 or WP10 universal app for blinking the Wifi into the Imp device, but there is a Windows version of it.
https://discourse.electricimp.com/discussion/comment/16357/#Comment_16357
This means the the blinking algorithm is already implemented with c# .net 3.5.
I could try to make this App, is someone just tell me how to blink the screen i.e. how to Encode the data to be send…