@Mike Smoak Thanks for posting in our Q&A.
Could you please try to visit the following link from the Safari, and to see if you can download the Intune Company Portal successfully.
https://itunes.apple.com/us/app/intune-company-portal/id719171358?mt=8
If not, on the device open up Settings -> Safari -> Block Cookies -> Make sure that is set to not block any cookies.
In addition, besides Intune Company Portal, can you install other apps, such as Outlook, OneDrive and so on?
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