Z-Mail and Nook?

My husband and I recently bought a Nook Tablet from Barnes and Noble (yay!), but it seems that Z-Mail does not work on the Nook.

I can get to the website and open mail fine, but replying to messages seems to be an issue. Any ideas what shortcuts I can take to access Z-Mail on the Nook? Would the mobile Zoho app work best?

Thank You ~ Grace