According to the AV-TEST Security Report 2016/2017, the number of malware samples detected in 2016 decreased compared to 2015, but they have been more sophisticated. The report was published by the independent anti-virus testing outfit AV-tEST. The research institute observed roughly 350,000 new malware samples each day, that correspond to four new samples per second. The number of Android malware samples doubled in 2016 to over 4 million. The majority of malware was Trojan, the majority of the majority was Trojan. Ransomware attacks peaked in the Q1 2017.”]
Source: http://securityaffairs.co/wordpress/60714/malware/av-test-report-2016-2017.html