This is the beach of Nas, in the west of Ikaria.
It's a relatively small beach, but the waves and currents are notoriously heavy. People have actually drowned in there, so if you don't consider yourself a good swimmer, then it's probably not the best idea to be in that water.
Why am I recommending it, though? Because Nas is one of the "trademark" beaches of Ikaria. An unorganized, raw beach where nudism is practiced and people hang out until it's sunset time. Sunsets are especially beautiful in Nas, as well as on the rocks right above the beach, where you will definitely see people standing in order to get a panoramic view of the beach and the Icarian Sea. There are a few tavernas right above the beach, all offering amazing balcony views.