Is there a solution for Collector to run on a Win8.1 tablet?
Currently Collector will only run on Windows 10
You can read Jeff Shaners comments in these blog posts which go over the reasons as to why the team went with a windows 10 solution.
Collector for ArcGIS on Windows 10 is now available! | ArcGIS Blog
Collector for ArcGIS on Windows 10 is in Beta! | ArcGIS Blog
Rope this helps you out.
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