At the current moment, we do not have a native application for mobile and tablets. 

We plan to release our iOS application in Q1 of 2013 and Android at a later time. 

In the meantime, you may access your Nimble account from your tablet or mobile device's web browser by going directly to your custom Nimble domain URL (example http://yourcompanyname.nimble.com or http://app.nimble.com).