iPhones are pretty good at giving you control over how much data apps can access. You can force apps not to track your data, and prevent them from needlessly accessing your location, microphone, and camera. But before iOS 18, when an app asked for access to your contacts, you had the option to scrape your entire address book or deny the app access to your contacts at all. That’s changed now, with the latest OS update letting you give apps access to just a few contacts.

The rule of thumb on the internet is that if you give apps access to your data, they will try to scrape almost everything and store it on remote servers until they no longer need it. Sure, there are apps that respect your privacy and stay away from unnecessary data collection. But some of the world’s most popular apps aren’t among them.

Let’s talk about social media apps. Under the guise of connecting you with your friends, apps like Gmail, Instagram, TikTok, Facebook, and many others will ask you to grant them access to your address book. Once you grant them access to that data, you can be sure that your entire address book is scraped and the social media companies know exactly who you’re connected to. This can lead to some fun outcomes, like connecting you with a long-lost childhood friend who you now cherish, but it can also be problematic.

The people in your address book didn’t give their consent for their information to be shared with companies that sell your information to advertisers, but those advertisers may now have their email addresses or phone numbers, plus a rough idea of who they’re connected to. Even if you really only wanted to find a select group of friends on social media, everyone in your address book is now likely to be recommended to each other as connections, without their consent. That ex you never want to talk to will likely come across your profile, or vice versa.