We do get several requests for a Windows option each week. The finite development costs mentioned are not the same as other companies as we us a universal code and can pretty easily port to supported platforms such as iOS, Android and Windows. Being on Windows, iOS, Android, Kindle, Nook are all part of our Universal App model.
Don't be concerned, our iFly GPS software is also built for and already running on Windows XP, Vista, 7, 8 and 10 without issue. It's ironing out the deployment to those windows devices that we are in a holding pattern for.