Protecting Data

Now that you have a good understanding of encryption, you can build on that foundation by learning additional ways to protect user data.


  • Activity: Preventing race conditions Video — 00:08:09
    • In this activity, we learn how to use good design to mitigate the risk of a race condition.

  • Inter-process communications, part 2 Video — 00:04:28
    • In this segment, we learn how to use locks and GCD queues to manage concurrency and mitigate the risk of deadlocks.

  • App backgrounding Video — 00:04:56
    • In this segment, we learn about the risk of exposure of sensitive data when an app goes into the background, and how to mitigate that risk.

  • Activity: Securely backgrounding an app Video — 00:11:52
    • In this activity, we implement in Swift a simple but powerful countermeasure to leaking data through app backgrounding.

  • Activity: Saving data in a realm database Video — 00:13:42
    • In this activity, we implement a Realm database in Swift.

  • Protecting files, part 2 Video — 00:07:24
    • In this segment, we explore the popular Realm database and how to implement it in Swift.

  • Common data risks, part 2 Video — 00:07:55
    • In this segment, we continue to look at risks to data, including common reasons for unexpected data leakage and how to mitigate those risks.

  • Inter-process communications Video — 00:13:59
    • In this segment, we learn what inter-process communications are and how Grand Central Dispatch manages concurrent operations. We study the two most common IPC risks to your data and how to mitigate those risks.

  • Activity: Storing an API key in Keychain Video — 00:09:11
    • In this activity, we learn how to securely store an API key in iOS Keychain.

  • API security Video — 00:11:52
    • In this segment, we learn what API security is and examine the various strategies for implementing that security.

  • Network security Video — 00:14:52
    • In this segment, we focus on how to protect data from unauthorized interception on the network and man-in-the-middle attacks.

  • Activity: Making an HTTP exception Video — 00:10:28
    • In this activity, we practice making an HTTP exception to the Apple’s App Transport Security.

  • Protecting files Video — 00:07:48
    • In this segment, we continue our discussion of protecting data. We focus on strategies for protecting user files in Swift and iOS.

  • Common data risks Video — 00:14:15
    • In this segment, we take a deeper look at risks to data, including common mistakes developers make and how to avoid those mistakes.


Course description

In addition to encryption, there are a number of other mechanisms you can employ to protect data. In this course you will learn about common risks to data, how to protect files, how ensure that data is transmitted over a network securely, and how to protect data from inadvertent leakage. You will also learn how to authenticate your app to an online data source, and how to use good design, code, and iOS features to ensure that processes do not interfere with each other, causing unexpected results.

Meet the author

Chrys Thorsen is a technology and education consultant with 25 years of experience. Her work has taken her around the U.S. and overseas, including as a contractor for the CDC using technology to help fight HIV/AIDS in Africa.

During her career, she has acquired 40 IT certifications, authored over 25 textbooks on a wide range of IT subjects, including secure iOS and Android coding, and created an equal number of IT-related video courses. When not working, Chrys enjoys reading scientific articles and experimenting with Internet-of-Things devices. She currently lives in Virginia with her sister, her cat and her dog which, as she describes it, “have the worst sibling rivalry imaginable.”

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