A little tip for all, especially the problems with the operation. BT pairing with Android OS have ...

Despite BT v4.0 standards on Android device pairing was not as intuitive as initially assumed.
Because it helps to already read the manual. On page 13 you can see the following:
"... If MOUS9 apparently does not work with your device while it is turned on,
hold the loupe and precision control buttons for 5 seconds until the blue LED flashes ... "
The key term there is attribution process to at DE on page 9 (see fig.)
With this workaround, it has for me then but still works and the mouse was successfully detected and coupled.
(Tested with Lenovo Yoga 10 Tablet Android v4.4.2)

While it was almost all addressed but for completeness below my short subjective rating;
First, the positive features:
+ Design / optics
+ Quality / robustness
+ Flexibility / Compatibility
+ Number of keys (10)
+ Keys programmable / adjustable via profiles
+ Ready-game and application profiles obtainable
+ Runtime / ergonomics (my expectations)
+ Customizable palm rest
+ Integrated storage compartment for the included BT USB Dongle
+ Beautiful exquisite packaging
+ Printed manual available
Included + AA battery for instant start-up in delivery

So now a pair of sub-optimal properties. which from perfectionism disconnect the Enprodukt:
o feel a little getting used to but ok
o sampling rate / resolution (could be a bit better than 990 dpi)
o pairing without Dongle not intuitive / easy
o Software (Windows) (optics is a matter of taste and function mostly ok but qualitatively it does not convince me)
o No possibility for calibrating mass by weight (but was known and no requirement)
o drivers / software not on disk while -> must first be obtained from the home page
o estimate the remaining battery capacity is similar to the algorithm used by the WinXP Explorer and is ... funny :)

Unique negative characteristics or KO criteria has this mouse definitely not for me personally, and therefore I can recommend this unique cyber mouse.