With all the personal information — emails, phone numbers, addresses, and financial details — stored on iPhones, iPhone privacy should be taken seriously. That's why you should set up Find My iPhone and know what to do if your iPhone is lost or stolen. There are other ways to control the privacy of your data, too.
Your iPhone is Not Secure – Do This Now!
In the past, several high-profile apps have been caught uploading information from users’ phones to their servers without permission. Apple has added features that control which apps have access to data on the iPhone (and the iPod touch, iPad, and Apple Watch). Most of these features are available in the iPhone’s privacy settings.
To keep the privacy settings on your iPhone up to date, check the Privacy section each time you install a new app to see if the app wants to access your personal data.
To find privacy settings, tap the Settings app and select Privacy. The Privacy screen shows elements of iPhone that contain personal information that apps can access, including Location Services, Contacts, and Calendars.