It looks like its working fine when I view it (using an iPhone). What phone are you using?
The only things I noticed is there is a lot of space after the logo in between the logo and primary nav.
I also noticed you’re using version 1.3 from viewing your stylesheet. If you upgrade to 1.4 you can use the responsive menu icons that work with the primary and custom menu/header right widget areas….have a look at the demo for an example – http://demo.appfinite.com/epik/
I don’t think it works with the secondary (menu on top) just yet.
Note: only upgrade if you haven’t made any changes to your theme files….if you have then you’ll need to carefully make your adjustments.