Device aware multifactor authentication with Citrix environment?

There are many services that advertise themselves as providing multifactor authentication for Citrix. But, most seem to require the additional generated passcode every time. Are there any that can require the password once per device, like Google's 2 step verification? So that once a device is registered, it only needs username/password at that point.

Components of this environment:

• NetScaler Access Gateway
• Storefront
• XenApp

I anticipate it would be the access gateway providing the mutlifactor aspect.