Fry (also Phry oder Phri, pronounced like free) is the capital as it holds the island's harbor. All the ferries arrive here. There are a few places where you can find accommodation. The village also has restaurants, a few places to shop and a post office.
Open all year around is the taverna Milos another good place is taverna "Kassos". To rent a room look for "Anessis" and/or the small guesthouse "Anagenissis". Both places are quite all right and reasonable. There are four other villages on the island (Agia Marina, Arvanitochrio, Poli and Panasgia). During summer there might be a bus otherwise you either walk or rent a bike in Fry. Last time there was no internet café on Kasos so be prepared to be offline.
There is little to see on Kasos. Some of the churches are interesting; there also is the Sellai cave. The latter is about 20 meters deep, interesting but not necessarily spectacular. You will notice that there are loads of little huts all over the island. They look as if they are used by shepherds and they most likely are.
The coastline is mainly cliffs. There are very few decent beaches; the one in Fry is OK though.
The main sources of income on the island are farming, fishing and tourism. In the old days the islanders were well known sailors. Their naval skills were actually feared by surrounding countries as the Kassiots kept interfering with their little plans. At some stage the Pasha of Turkey was so pissed off with them that he sent his naval fleet to the island and got all inhabitants killed.
Kasos was annexed by Greece in 1948. There are daily flights to Rhodes and Karpathos. There are 3 ferries a week from Agios Nikolaos and Sitia on Crete. They actually go to Karpathos and Rhodes but stop in Kasos. To Karpathos it takes about 1.5 hours, to Rhodes 6 to 7. Crete is 3 – 5 hours away.