The report mainly focuses on detailing PHA rates in various markets, Android versions and countries. It counts PHA rates by scanning 50 billion apps daily from inside and outside of Google Play using Google Play Protect. The report states that the PHA rate has been on a steady decline year on year, and it averaged a lower PHA rate of 0.08 percent in 2018's first three quarters. To compare, in 2017, on average 0.09 percent of devices that exclusively used Google Play had one or more PHAs installed.
Google also notes on its blog that the PHA rate continues to steadily decline on phones that have the newer Android version installed. This is because of 'continued platform and API hardening, ongoing security updates and app security and developer training to reduce apps' access to sensitive data. In particular, newer Android versions-such as Nougat, Oreo, and Pie-are more resilient to privilege escalation attacks that had previously allowed PHAs to gain persistence on devices and protect themselves against removal attempts,' the company explains on its blog.
Furthermore, the report states that India saw the most significant decline in PHAs present on devices, with the average rate of infection dropping by 34 percent. Indonesia, Mexico, and Turkey also saw a decline in the likelihood of PHAs being present on devices in the region. South Korea saw the lowest number of devices containing PHA, with only 0.1 percent. You can view the report here.