Hey Harald-René (or is it Flasch? I couldn't find good information about Austrian names, no offence intended!),
"Detailed Device Information" is simply a dump of all of the information that we have about the specific device. You can get to it by clicking on the device name (top right) while connected (and expanding the "Information" expander)
"Devlop[er] App Control" (well spotted on the typo!) - as the rest of the text states, this simply means that you can launch and kill developer apps directly from the UI. This can be useful in demos or if you have a lot of developer apps which are all GUIDs
it can be useful in distinguishing which app is which.
Regarding documentation, I might add a bit if I get a chance, otherwise I'd rather try to make the product a little clearer :)
Thanks for the feedback!