Hi and welcome to the forum and the world of Inspires.
Yes you will need to run the GO app on both, the general idea being that with dual remotes the master is for the pilot and the slave for the camera operator. One thing to be aware of (unless the latest update has changed it - which I need to check) is that if the slave RC operator reviews a photo or video mid-flight, the master RC screen will also show the photo / video thereby losing the live flight telemetry and live camera view. Once the review is closed then the screen reverts to normal. I run a Hudl 2, an iPad air and an iPad mini 2 quite successfully and apart from the above, if one hangs up (ocasionally the Hudl) the other isn't affected.
I usually connect the better tablet (iPad air) to the slave as the camera operator needs the better picture and the minimum of video lag which can be a problem with some android tablets though this seems to be improving with software updates.
I bought a Hudl as a second tablet but once the GO app was launched a problem appeared whereby the app crashed. See here:
DJI GO on hudl 2 | DJI Inspire Forum
also on Phantom Pilots forum:
Professional - Hudl 2 with dji go | DJI Phantom Forum
Until you get your Inspire and become familiar with the app this may not make sense but the problem can be overcome albeit with the loss of the video caching feature. The latest updates haven't fixed this problem though I hope that a future Hudl update may do so. As the Hudl is unlikely to be a supported device my fear is that problems will continue to arise from time to time and so I invested in the iPad mini 2 as my main tablet. At least with the iPads they are supported by DJI and are all share the IOS platform from the one manufacturer unlike the multitude of android devices. It also seems that new features appear first on the IOS devices and I believe the simulator still isn't yet available for android tablets. It also seems to me from reading posts that the IOS devices have the edge in terms of display quality and video performance (viewing, not recording).
Lots of threads on tablet choices on this forum (and Phantom Pilots) so do your research but I have to advise against a Hudl 2 - learn from my mistake. If you go for an iPad just make sure it's compatible - needs to be an iPad air or later and an iPad mini 2 or later, earlier versions aren't compatible. Of course you can also use an iPhone 5s or later but with a screen smaller than a 6+ it may be a struggle.
Good luck and enjoy your bird.