They're being marketed to pilots as chart readers. They come with reader software that supports the Jeppeson chart format. But they also come with the original Epub and PDF support, and from what I can tell, they're not locked down. You should be able to install other apps (like FBReader).
The list price is $1,195 for the DX8 and $1,595 for the DX10. Yes, that is indeed $800 more that the retail versions.