Published August 27, 2016
If you have an iPhone, Apple recommends that you upgrade to iOS 9.3.5 as soon as possible. With previous versions of iOS, there are multiple zero-day vulnerabilities that can allow someone to take control of your device’s camera or microphone.
If you device isn't upgraded, there are numerous apps that a hacker could monitor or use, including iMessage, Gmail, Viber, Facebook, WhatsApp, Telegram, Skype, Line, KakaoTalk, WeChat, Surespot, Imo.im, Mail.Ru, Tango, VK and Odnoklassniki.
This critical update is available from Apple. To install the update on your iOS device, launch the Settings app, then tap General > Software Update. You also can update within iTunes with your device connected to your Mac computer.