OrchardNest

A couple of months ago, I released a new app called Dependencies on the Mac App Store. You can download and try it for free at https://apps.apple.com/app/dependencies/id1538972026. In this article, I explain how I built the command line...

If you followed the recent Apple events, you probably saw a picture of the A14 and M1 dies… that got me thinking about what you would see if you could pass iOS under X-Rays… In my previous article about the evolution of the programming...

In my previous article about Apple’s use of Swift and SwiftUI in iOS 14, I counted the number of built-in apps in iOS using Swift and SwiftUI. Several readers asked if I could provide a percentage rather than an absolute number. In this...

Swift was introduced a couple of years ago at Apple’s 2014 WWDC. Over the years I analyzed iOS to measure how many built-in applications were using Swift. iOS 9 released in 2015 included a single application written with Swift:...

Assiduous readers of this blog might have noticed a significant drop in the number of articles last year. Couldn’t I find any interesting subject? Was I getting lazy? Hell no! Today I am pleased to release Clatters for iOS and...

Swift was introduced at Apple’s 2014 WWDC and it is interesting to measure Apple’s own use of Swift in iOS over the years. iOS 9 released in 2015 included a single application written with Swift: Calculator. Since then the number of...

Using a VPN is an obvious solution when you are connected to internet on an untrusted network. Instead of paying a subscription to a VPN service, I decided to create my own VPN server. It turns out that this is much simpler than I...

Lately, many people have wondered why some iOS apps were so huge. I asked myself this question and analyzed the Facebook application for iOS v. 66.0 in 2016 and v. 87.0 in 2017. In this article, I dissect the Nest app (5.30.5) for iOS...

libMobileGestalt is a private library in iOS that describes the capabilities of the device: system version, build version, device type, device features, status of the airplane mode, … Apple obfuscates this information which makes it...

A QuickLook plugin on macOS 10.14 has several constraints to satisfy. If one of the limits is exceeded, the plugin will immediately be killed and no preview will be visible. Having such restrictions makes sense but they appear to be...

In a previous article, I reverse-engineered the .car file format used to store the compiled assets of an Asset Catalog. I also demonstrated how to create a tool to manually parse such files. While this tool can extract a lot of...

An Asset Catalog is an important piece of any iOS, tvOS, watchOS and macOS application. It lets you organize and manage the different assets used by an app, such as images, sprites, textures, ARKit resources, colors and data.

Two years ago I measured Apple’s use of Swift in iOS 10.1 and last year I counted how many applications were using Swift in iOS 11.1. This year I’m analyzing iOS 12, released by Apple this month.

In this post I present VPNStatus, an application that replicates some functionalities of macOS built-in VPN status menu:

macOS 10.13 contains a built-in VPN client that natively supports L2TP over IPSec as well as IKEv2. In this post I describe some parts of the internal architecture of the macOS VPN client. This information will be used in a following...

A year ago I analyzed how many built-in apps in iOS 10.1 and macOS 10.12 were using Swift: Apple’s use of Swift in iOS 10.1 and macOS 10.12. How many built-in apps are using Swift in iOS 11.1 and macOS 10.13.1? Let’s find it out!

In this article, I discuss the dangers of force unwrapping and how to avoid forced unwraps.

This post follows up the Analysis of the Facebook.app for iOS [v. 87.0].

In this article, I analyze the version 87.0 of the Facebook.app for iOS.

/usr/lib/libMobileGestalt.dylib is a private library which provides an API to retrieve the capabilities of the iOS device, as well as some runtime information: system version, build version, device type, current status of the airplane...

Ian Beer did an incredible work with his iOS 10.1.1 exploit. The mach_portal proof of concept gives you a root shell on iOS 10.1.1. You can read more about it here: https://bugs.chromium.org/p/project-zero/issues/detail?id=965 While...

Let’s say you pick a random pointer. Can we know if it points to a valid Objective-C object? Of course without crashing… Well there is no simple solution. In this post I give a solution for 64-bit architectures. The code...

Swift has been announced at the WWDC 2014, more than 2 years ago. Most of the sample code projects from Apple are now written in Swift. But does Apple use Swift in iOS 10.1 and macOS 10.12.1?

Did you ever wonder why the Facebook.app for iOS is such a big download? This post tries to give some answers. The version 66.0 (released on 7 October 2016) was analyzed on an iPad Air 2 (64-bit).

In iOS 10 Apple added a new dedicated setting for Temperature Unit in the Settings.app under General > Language & Region > Temperature Unit . It lets you switch your preferred unit between Fahrenheit and Celsius:

In a previous post CryptedHelloWorld: App with encrypted mach-o sections, I created a simple macOS app CryptedHelloWorld with its (__TEXT, __text) section encrypted. The section is decrypted by a constructor function. This post explains...

Mail.app in macOS 10.11 and earlier used to check the plugins compatibility using the SupportedPluginCompatibilityUUIDs key in the plugin’s Info.plist. For example a Mail plugin would only be compatible with macOS 10.11.6 if its...

In a previous post ( constructor and destructor attributes ), I described the constructor attribute and mentioned software protection as a possible use case: A constructor attribute could be used to implement a software protection. You...

GCC (and Clang) supports constructor and destructor attributes: __attribute__((constructor)) __attribute__((destructor))

Until macOS 10.11.4 and iOS 9.3.1 CommonCrypto/corecrypto supported Blowfish operations with key sizes longer than 448 bits. Starting with macOS 10.11.5 and iOS 9.3.2 this is no longer the case: the minimum and maximum key sizes are now...

The State Preservation and Restoration system is well documented here: Preserving Your App’s Visual Appearance Across Launches. But what is not well known is that there is a secret preference to enable debug logs.

Let’s say you want to have a different behavior in your app depending on whether you build it in Xcode or you perform an Archive. And you want this behavior to be done at compile time. Note that the use of different configurations is...