Zipolite's beach is huge, running for a good 1.5km and dispatching massive waves. It's famous for its nudity; you'll see people randomly swimming, sunbathing or happily walking across the wet sand minus their clothes at any time of day, although it is more common in a couple of coves at the western end of the beach and in the small bay called Playa del Amor at the east end, which is a favorite spot for gay men.
The eastern end of Zipolite (nearest Puerto Ángel) is called Colonia Playa del Amor, the middle part is Centro, and the western end, where most of the traveler scene is centered, is Colonia Roca Blanca, where you'll find what amounts to the main street, Av Roca Blanca (also called El Adoquín), a block back from the beach.
Surfing is better toward the west. For more seclusion and the best boutique hotels, retreat to the far western end of the beach behind several rocky knolls.