The list of supported devices is released by Microsoft and yes, the number is very limited. But Microsoft has its own reasons a to why they couldn’t make it to the high-end devices yet.
The reason why only a limited number of devices are added to the first preview program. Microsoft mentioned, “is to isolate OS issues from hardware or board support package issues so we can stabilize the platform.”
On an explanatory note as to why high-end devices are not added to the program yet, Gabriel Aul said:
We have a feature that will be coming soon called “partition stitching” which will allow us to adjust the OS partition dynamically to create room for the install process to be able to update the OS in-place. Until this comes in, we needed devices which were configured by mobile operators with sufficiently sized OS partitions to allow the in-place upgrade, and many of the bigger phones have very tight OS partitions.
If you own a Windows Phone 8.1 device that is not yet included in the Technical Preview, you need not worry much as Microsoft mentioned that with each new build, more devices would be added.
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