Signature & Verification + Secure Enclave

Thanks to Lukas for the illustration

A digital signature is a guarantee to the receiver regarding the authenticity, integrity, and verification of the sender. To simply put, it’s equivalent to a handwritten signature. A digital signature is achieved using a different key pair than the one used for encryption/decryption.

Digital signatures are utilized in many electronic aspects, Xcode does digitally sign your code whenever you’re to submit your app for testing or to the app store. In general, this is how a sender signs the data to be sent:-

  1. The sender encrypts his/her data with a specific hash algorithm (ex: sha256). …


Thanks to drawkit.io for the nice illustration

On March 25th 2019, Apple announced its new consumer U.S. credit card issued by Goldman Sachs “Apple Card”. They pointed out that for every Apple Card, there’s a unique per device card number that is created and stored safely in the device’s secure element & that every purchase is authenticated with Touch ID or Face ID.

The purpose of this tutorial is to further elaborate what is the iOS device’s secure element Apple pointed out during their new Card announcement and how developers can utilize it for purposes that have to do with their applications.

First, let’s go through some…


In the first and second parts of this three parts tutorial, we’ve covered how to utilize Xcode breakpoints to manipulate an existing property value and inject a new line of code via expression statements. We’ve also explored watchpoints that are a special type of breakpoints.

I developed a demo project with several intentional bugs to elaborate on how to use different types of breakpoints alongside the LLDB to fix bugs in your project/application.

If you didn’t go through part 1 and part 2 of this tutorial, it’s crucial to check them before proceeding with this final part.

One last time…


In the first part of this three parts tutorial, we’ve covered how to utilize Xcode breakpoints to manipulate an existing property value and inject a new line of code via expression statements.

I developed a demo project with several intentional bugs to elaborate on how to use different types of breakpoints alongside the LLDB to fix bugs in your project/application.

If you didn’t go through part 1 of this tutorial, it’s crucial to check it before proceeding with this part.

Let me remind you of the golden rule of this tutorial: You’re not to stop the compiler or re-run the…


One of the very intriguing sessions carried out by some of Apple’s finest debugging engineers during 2018’s WWDC was Advanced Debugging with Xcode and LLDB. They informed us about some impressive tips and tricks on how to utilize Xcode’s breakpoints and low-level debugger (LLDB) to optimize the debugging process whenever it happens that developers encounter bugs and all out to fix them.

In this 3 parts tutorial, I’ll walk you through most of what has been concluded in that WWDC session. …

Fady Derias

iOS Developer, BSc Mechatronics Engineering.

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