is it possible to build something similar but "digital" for midi controller?
(thus, it can read the Level meters from Logic, cubase, etc..)
it depends on how you can make those apps send you your information. if it's midi no problem, but if we're talking about analog audio (from a headphones jack for example) you can try hooking it directly to some analog pin on your board plus ground to ground. note that the signal will between -1V and + 1V (i think) so you may need to amplify it to use the full range of the analog port (0-5V).