Let’s start with the good news: most iPhone users don’t have to worry about their phone getting a virus. It’s rare, and there’s really only one scenario in which an iPhone can get a virus.

While it is technically possible for iPhones (and iPod touches and iPads, since they all run on a similar operating system) to get viruses, the chances of that happening are very slim. There have been only a few iPhone viruses developed, and many of those were created by security professionals for academic and research purposes and have not been published on the Internet.

Viruses are programs designed to do malicious things — like steal your data or take control of your computer — and spread themselves to other computers. To achieve its goal, the virus must be installed on your phone, be able to execute, and also communicate with other programs to obtain their data or control them.

The architecture of the iOS operating system doesn’t allow apps to do this. Apple designed iOS so that each app runs in its own, limited “space.” While iOS apps can communicate with each other, they are limited in their ability to do so. By limiting the ways in which apps can interact with each other and with the operating system itself, Apple has reduced the risk of viruses on the iPhone.