One of the best features of the old Navmonster.com website is it would display a chart of your enroute times calculated at different altitudes based on the winds aloft report. This was invaluable for selecting which altitude to fly on a specific trip.
The iFly has all the information needed to do this - it would be a terrific feature in flight planning to have the iFly display a chart of ETE times for different altitudes for your entered route.
Thanks,
Steve