Why does the iPhone gem store always have offers but not windows?

I know you say you cant implement certain things in the game but I’m sure that’s not one as when I started the app I bought 1050 for around £3.99 but its never been that price for me since but it is most the time on the iphone. Giving we don’t get the tapjoy/video gems isn’t that one thing you can give us not so iphone players can basically get heeps of gems. I currently have 46. That £3.99 deal would do nicely. Haven’t had a “special offer” for a while either