Windows Phone 8 is well over a year old now, yet we still know very little about Windows Phone 9.
Originally it was expected to be with us by the end of 2013 as it was thought that Microsoft may adopt the annual software cycle made popular by Apple in an attempt to keep its mobile OS fresh and, more importantly, relevant.
That didn't happen, but from the information that we've been able to gather so far it looks like Windows Phone 9 could be a massive overhaul, so it's not surprising that it's taken over a year.
However we did recently get Windows Phone 8.1 to tide us over, while leaks highlight that Windows Phone 8.5 may also be on the cards.
Before we get our teeth in Windows Phone 9 we need to visit the rumors surrounding version 8.5. It's been confused with the ninth iteration of the platform before, and it's important to make a distinction between the two.
Windows Phone 8.5
It looks like there might be such a thing as Windows Phone 8.5 in the works, but details are slim on the ground. All that's really known so far is that there will seemingly be some potentially quite substantial changes to the Start screen interface in Windows Phone 8.5, but there's no word yet on what form those changes may take.
It's also worth noting that while we list this as a Windows Phone 8.5 feature it's entirely possible that it may end up in Windows Phone 9.