Malware madness: Here are the top 5 most malicious apps in South Africa A recent report found that 1 in 6 mobile devices in developing countries are infected with malware. SA has five apps that are particularly malicious. An ominously titled report by leading mobile technology company Upstream found that one in six Android mobile devices in developing countries were infected with malware in 2021. A Pandemic on Mobile—Mobile Ad Fraud and Malware said that the COVID-19 pandemic exacerbated the problem because people across the globe were suddenly forced to conduct more and more of their lives online and fraudsters capitalised on it.