Which side of Zanzibar is best to stay on?

The best side depends on travel style. The north coast around Nungwi and Kendwa is popular for swimming, sunsets, and a lively atmosphere. The east coast around Paje, Jambiani, Matemwe, and Pongwe is excellent for scenery, kitesurfing, quiet stays, and boutique lodges. Stone Town is best for history and culture. Many itineraries combine Stone Town with a beach area.