I've had Windows phones for many years, since Windows Mobile 5.5
The last (the first HTC Touch) was exhausted before Windows 7 came around.
I've sticked with HTC Desire Z and tried android out.
This phone is almost dead after 3 years (no WiFi, bad bateries), but I keep recharging it just to use Ovuview!
Together with wat was first an excel sheet, I have more than 4 years of period tracking at you beautiful app.
Please, when are you planning a new version for the blooming Windows 7.8/8 community?
It didn't even need to start with all the cool graphics. Just your calculations, based on previous periods, is already unique!
This is the only app I've spent money on at android, and I would pay again at Windows.
Don't give up on your happy customers just because they gave up android...