If you go to Zanzibar or, alternatively, the Maldives, the Seychelles, Reunion or Mauritius, you obviously look for nice weather, sandy white beaches, pristine waters and perhaps, a bit of fun. Indeed you will find all of these in Zanzibar. Eastern beaches are wide stretch for almost 40 km, the water is clear, and if you can avoid the hassle, people are very friendly.
If this is what you want, remember the Eastern part of the island is subject to strong tides and depending on what time of the year you go you may not be able to swim - you can go in for almost a km before you get water on your waist. Still, it is worth visiting as it is quiet and relaxing during the day - much less at sunset. The northern part around Kendwa is probably the best choice is you want to sit, relax and do little more. There is a beach also in Stone town. It is small, crowded and from 4pm on the local go there to play volleyball, football, and do acrobatic performances; so there is not much space left to lay down.
Zanzibar has a rich cultural heritage - mainly Portuguese but also Arabic. Unfortunately, monuments are not well kept, indications of where they are located are random, and the few I managed to find were closed. A pity. Stone town is a bustling city, worth staying a couple of days. The best is to wander in the tiny street of the old town and admire buildings, doors, windows and locks.
Probably many know the biggest celebrity of Zanzibar: Freddy Mercury. There is a house museum in the center of Stone Town, but it just contains pictures and a few objects and I decided not to go. Instead I eagerly tried to find the house of the other famous Zanzibarian I know: Abdulrazak Gurnah, Nobel price for literature in 2021. After many turning around in the stress of the old Stone town I gave up and instead sat at a cafe to read his novel By The Sea. 😀