Exynos devices exhibit Samsung's greatest disdain for developers. Samsung goes well out of their way to be a PITA by using crappy KNOX in the bootloader and everywhere else. Also the Exynos devices aren't sold in great numbers and not sold at all in North America so many devs don't want (or can't) to take the time on a rare device.
It's too bad bc I see them going on ebay for $350-ish.
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