iGUI drop-own list does not work on Windows Phone 8

Dear unity Community,

I implemented an iGui drop-down element on my scene with various options to choose from. The drop-down list is just working fine in game mode, but it is not working as an app on Windows Phone 8. I also tested in on Android and it worked.

Do you have experienced the same problem? Do you have a solution for the problem?

Thank you in advance!