Apple’s devices are more secure than Android, according to most studies. iPhone users benefit from a development team that focuses on user experience and security. Apple has what is known as a “closed development OS,” which means hackers cannot view source code and security holes.
5 Tops Possible Vulnerabilities of your iPhone
App Security and Versioning
Daily, the average person uses between 10 apps and 30 apps per month. It's not uncommon for over 80 apps to be downloaded to a phone. While you may not use these apps or even forget that you downloaded some of them, they do pose a security risk.
If an app has a security hole that goes undetected, it’s plausible that someone will decide to take advantage and begin exploiting it.