Hi friends,
i wanted to know, if i can run ardour on my android-tablet with touchscreen; i wouldnt need the touchscreen, though i can use external keyboard, but is there a ardour version running on android?
thanks in advance?

No, Ardour does not run on Android, and there are no plans to port it. There are remote controllers for Ardour + Android, but not Ardour itself.

thank you paul! I just bought now a windows tablet, which i can use as a laptop and which can run ardour too; the only thing now im afraid: my Ubuntu STUDIO 16.04 runs now perfect with ardour 4 (sic!!!)! Yes, with ardour 5.4. i had ALL THE TIME problems; im worrying now, when i use now a newer version on the tablet, i cant open projects of ardour 4, is that right? For example, with my ardour 4 (ubuntu studio 16.4 on PC) i cant open ardour 5.4. sessions i already created before …
OR WOULD YOU SAY: Our actual Ardour is now much better and stabile than Ardour 5.4.???
thanks for your answer!!!

Sure, version 5.11 is ahead of 5.4 and bugs have been fixed, but the same holds for 5.4 versus version 4. When you have problems with 5.4 on Ubuntu 16.4, is that in the build that’s supplied from the Ubuntu studio repository? if yes, that’s most likely your problem right there, a lot of Ardour builds supplied by distributions are not 100% functional. Your best option is to download the latest release version from this website (and yes, you have to make a payment and that’s only reasonable).
The second best option is to download the source, and build it yourself, but you will spend considerable time reading documentation, installing dependencies, and configuring before everything works smoothly, particularly video playback and plugins etc.
Ardour runs fine on Windows, my daughter has a wonderful Windows 10 2-in-1 ultrabook but we’ve never attempted to flip it into tablet mode for using Ardour, you would probably struggle to use it for more than very basic things, as the user interface is designed for 2-handed use with a keyboard and a proper mouse (that is, one with a wheel and 2 buttons).
The features which make up for some of the shortcomings of a tablet, multitouch, gestures, on-screen keyboard etc., aren’t suited for Ardour.