Does iOS encrypt all the data on my device when I set a passcode to my iPhone Excuse my stupidity, I know less than nothing about mobile phones OSes but I have been told that iOS encrypts your data when you set a passcode to your phone. This means even if someone stole your phone, took the storage unit out of the phone and mount it he will NOT be able to to examine your data as it encrypted. Something similar to what *nix OSes do when you choose to encrypt your home folder during the installation process.

My concerns are:


What type of data does it encrypt? it's hard to believe that my iPhone decrypts all my photos once I enter my passcode (assuming that iOS encrypted them)
How difficult is it to crack an encryption that is based on simple four digits?!
Yes, your iOS passcode will encrypt your phone's data.


  Data protection enhances the built-in hardware encryption by protecting the hardware encryption keys with your passcode.


Source: iOS: Understanding data protection

Whilst it was generally unclear exactly what was encrypted in older versions of iOS, Apple have made it clear in their new privacy policy with regard to iOS 8:


  On devices running iOS 8, your personal data such as photos, messages (including attachments), email, contacts, call history, iTunes content, notes, and reminders is placed under the protection of your passcode.


Source: https://www.apple.com/uk/privacy/government-information-requests/