simultaneous touch events trigger only the first touch

[Andreas E.]

expected behavior:
When I do a key combination (like shift+a or ctrl+s), I would naturally put finger 1 on "ctrl", then finger 2 on "s" and then release both, as I am used it from a physical keyboard. It is also working like that on various touchscreen phones.

observation:
The first/single touch is recognized but the (added) second touch does not yet trigger the "s". The ctrl key stays in highlighted mode and waits for another separate input of "s".
Instead of simultanously touching both keys, I need to touch them consecutively.

Ubuntu 14.04
onboard 1.0.1+1811-0 amd64

[marmuta (marmuta)]

Multi-touch in Onboard is supposed to work as you described, Andreas. I heard of people successfully using it in the wild too.

Please check if
Preferences->Keyboard->Advanced->Touch input
is set to multi-touch. This is the default.

Check if you own a Wacom touch-screen. Those are by default configured to not allow multi-touch, see also bug #1297692.
$ xsetwacom --list devices

If this returns your touch screen you'll have to disable Wacom gestures in order to get multi-touch.
$ xsetwacom --set <your touch-screen id> Gesture off

You can use the output of the "xsetwacom --list devices" command as id, or pick it from
$ xinput

[Launchpad Janitor (janitor)]

[Expired for onboard (Ubuntu) because there has been no activity for 60 days.]