I think the APP you want to look for is called ( DIRECTV Nomad ) I do not believe there is one called GenieGO and if there is one it is probably unrelated to DIRECTV or something else.
Please note the NOMAD was just recently rebranded GenieGO but some rebranding of names such as in the APPS may still be in the works by the DIRECTV marketing team or IT guys.
OP: I have the same issue on my Asus Transformer. It's listed as compatible on the DirecTV website, but not according to the Google Play Store. I called tech support, but they weren't able to help. They recommended I come to the forums, but I've been told by other posters that the forums are not monitored by DIrecTV. My last attempt was to send an E-mail to DirecTV Support that said: "Could you please notify whoever is responsible for posting your app to the Google Play Store that the ASUS Transformer Pad is not listed as "compatible". I believe it is something DirecTV has to enable when making the app available."
The response via E-mail was "Thank you for writing about the ASUS Transformer Pad.
I understand that access to these application is important to you, however, at this time, we do not have any plans to support this application.
Your thought matters. Thus, I have forwarded your suggestion on to DIRECTV Management for review. While DIRECTV Management can not follow up individually with every customer, rest assured every suggestion and comment is reviewed. We often make changes based on customer feedback like yours."
So, no joy directly from DirecTV. The app does install on the Transformer, however, and it might on the Galaxy Tab 2 as well. I installed the app on my phone, backed up the app (using MyBackup Pro), and then transferred the APK file to my Transformer and installed it. Round about way of doing it, but it worked.