When I hold down a key on a regular keyboard, the key gets repeated over and over. I do see the advantages of that for an electrical typewriter. On Android (and other glass pecking devices) when I hold down a key it shows me letter variations like u ü û ů.
Is there such functions for Ubuntu? Show the variations with a number next to it (left, right, top, below) like double byte input and insert on number or click?
Update: Mac OS/X does exactly that. If that's part of Darwin (??) it could be ported?
I didn't find the onscreen keyboard like on OS/X, but a close second, fulfilling my special character needs. When you use English (international with AltGr dead keys) you can type the special characters in two ways. AltGr is usually the right Alt key (in continental European keyboards labeled AltGr):
So a bit of a learning step but close enough for daily use (see also). For viewing the keyboard on screen check this askUbuntu answer.