This is a sign posted up at the YWCA in Dar Es Salaam, Tanzania.
In Dar Es Salaam, it did felt a bit unsafe to stay out too late at night. And there were lots of people who would greet you with the standard greeting (usually “Mambo” or “Jambo”) and they would wait for your greeting back (reply with “Poa” or “Jambo” - respectively"). Even when you get tired of saying it, they will try to teach you to say it again and again. Mostly it felt like a passing-by type greeting, and no intention behind it.
I also went to Kariakoo in Dar Es Salaam, supposedly Africa’s largest covered market, though you’d be disappointed coming from Asia or Thailand (Chatuchak much much bigger). There was nothing much there, and it basically didn’t feel safe there. I heard a lot of them shouting “Cina! Cina!”. And although I was very careful with my belongings and camera (didn’t dare take it out to snap some pics), someone still manage to try and grab my gold chain. He managed to snap it, but his stubby fingers didn’t manage to grab it. Scarily, he just stood there and stared at me while I was wondering what happened and walked away. It was broad daylight and crowded!
However, that said, the other parts of Tanzania felt safe – in Zanzibar or Mikumi. Though you’d still hear the Mambo Jambo everywhere, and some hassles as usual in touristy places. And oh, most people don’t like their pictures taken too. But you can feel that many of them were genuinely friendly.