Most areas that tourists venture to are safe and the likelihood of a tourist becoming a victim of violent crime in South Africa is low. South Africa overall has a travel advisory with a recommendation to exercise a high degree of caution due to the level of serious crime.
Robberies are often reported on roads and at shopping centres and for the most part, public transport should be avoided. Crime rates are higher after dark, particularly in major city centres, isolated beaches, lookouts and township areas. ATM scams also occur and it's important to avoid using ATMs that open onto a street. Find a bank if possible and keep your withdrawals to a minimum.
In South Africa, you can really benefit from the following features of a policy; emergency medical expenses, cover for luggage and personal effect, cover for your travel documents (including passport and credit cards), theft of cash and hijacking.