Preserving Tsakonian, the only descendant of Doric Greek with only about 300 speakers left
"At the beginning of this year, a few dozen eager primary-school students ascended the mountains near Leonidio, in Greece’s Peloponnesus, tape recorders in hand, to visit cliffside hamlets accessible only by narrow and impossibly steep roads. Their task: to record conversations with residents old enough to be their great-grandparents – the last few fluent speakers of Tsakonian."
I heard about this kind of Greek two days ago on my first day in Koiné Greek class at the university. This article is very interesting.
The article states
Currently, Tsakonian uses Greek letters with special diacritics, or accents and other marks, that are not recognized by computers and mobile phones. That should change, Kisilier says, to a Tsakonian alphabet in which distinct phonetics are written with a combination of existing Greek letters.
but given the content of the Wikipedia article on Tsakonian, the diacritics are recognized at least by computers, although they may not be straightforward to type. The system of digraphs (and trigraph) that Kisilier recommends is the older orthography.