What are some good on-screen keyboards for Linux?

Question

Gnome

I read the article: geektimes.ru/post/246826 I was
delighted, and I installed Gnome3 on our new x220 tablet. Since the transformer is not only mine, but also my young man, I put there not gent or fedora, but Ubuntu Gnome 15.04
Results:
1) onboard worked at first, now it does not work. The strangest glitch, the touchscreen works, but if you press the keyboard, it starts blinking with all the buttons, and press any buttons except those that are poked
2) onboard, when you poke in the input field, it pops up 1 time out of ... 10? Or after incomprehensible manipulations with onboard-preference? In general, I can not reproduce what he needs.
Is this an issue with Ubuntu 15.04, onboard, or something else? The built-in keyboard in Gnome, when you log in through GDM, seems to work fine.
Should I change 15.04 to LTS 14.04, or onboard to another keyboard?
3) a strange glitch also arose when I dealt with the tach, some gnome utility was accidentally called up, probably, but now under my user everything was skewed, and it became a small font, and the Gnome windows did not fit on the full screen. All is well under another account. Of course, I can hide all files and directories starting with a dot in my account and related to Gnome, after that it will obviously be fixed, but it scares me that this situation can happen again.
KDE[234], Gnome2, Unity, Openbox stadalone, Openbox +LXDE, XFCE - I've never seen such strange bugs in them. Well...maybe except early KDE4