Open Source Objective C Debuggers

FLEX (Flipboard Explorer) is a set of in-app debugging and exploration tools for iOS development. When presented, FLEX shows a toolbar that lives in a window above your application. From this toolbar, you can view and modify nearly every piece of state in your running application. Access any live object via a scan of the heap. View the file system within your app's sandbox. Browse SQLite/Realm databases in the file system. Trigger 3D touch in the simulator using the control, shift, and command keys. Explore all classes in your app and linked systems frameworks (public and private). Unlike many other debugging tools, FLEX runs entirely inside your app, so you don't need to be connected to LLDB/Xcode or a different remote debugging server. It works well in the simulator and on physical devices.

The Pajé visualization tool provides interactive and scalable behavioral visualizations of the dynamics of the executions of parallel and distributed applications.

99eyeballs is a tool that helps developers using Mac OS X Apple’s Cocoa frameworks find inconsistencies in the retain count of Objective-C cocoa objects.

CUT is a simple, to-the-point unit testing system. It's different from other unit test packages in that it follows the KISS principle. It's designed for C testing, not designed to emulate SUnit.

A program to apply a link map to a Mac OS X crash log that came from a build without traceback tables. The output contains at least as much information as would the same crash log from a corresponding build with traceback tables.

HeapInspector is a debug tool that monitors the memory heap with backtrace recording in your iOS app. You can discover memory leaks, no longer used objects, abandoned memory and more issues directly on your device without ever starting Instruments. Basically, you can inspect the entire heap and see all living objects of your iOS app. To be more precise you can record the heap for a specific part of the app. For instance when navigating through the menu. Like in Apple's Instruments the snapshot compares the heap before you started recording. For instance you can start the snapshot before you push a new UIViewController onto your UINavigationController stack and stop after popping the UIViewController.

LLDebugTool is a powerful in-app debugging tool for iOS that provides detailed insights into app performance, logs, network requests, and crash data. It offers a floating window for developers to monitor the app in real-time without external tools.

Tools for Palm OS developers on Mac OS X. Cocoa Palm Reporter logs traces emitted by the Palm OS Emulator. USB-TCP Bridge provides a socket that can be used to communicate with a Palm handheld over USB (for example, GDB).

NetworkEye, an iOS network debug library, monitors HTTP requests. It can be detected HTTP requests including web pages, NSURLConnection, NSURLSession, AFNetworking, 3rd libraries, 3rd SDK, and so on. very convenient and practical. It can be a map local json file.

PonyDebugger is a remote debugging toolset. It is a client library and gateway server combination that uses Chrome Developer Tools on your browser to debug your application's network traffic and managed object contexts. To use PonyDebugger, you must implement the client in your application and connect it to the gateway server. There is currently an iOS client and the gateway server. PonyDebugger sends your application's network traffic through ponyd, PonyDebugger's proxy server. You use Inspector's Network tools to debug network traffic like how you would debug network traffic on a website in Google Chrome. PonyDebugger forwards network traffic, and does not sniff network traffic. This means that traffic sent over a secure protocol (https) is debuggable. Currently, the iOS client automatically proxies data that is sent via NSURLConnection and NSURLSession methods.

GBA Debugger for Mac OS X and GNUstep

XcodeColors is an Xcode plugin that adds colored output to the Xcode debugging console. It was created to make logs easier to read during development by highlighting errors, warnings, or logical sections of application output. Developers can specify exact RGB foreground and background colors from their own source code. The project supports manual escape-sequence usage, custom macros, CocoaLumberjack integration, and CleanroomLogger integration. It was built for older Xcode versions, including Xcode 3 through Xcode 7, so it is best treated as a legacy debugging utility. The repository remains useful as a reference for historical Xcode plugin development and console log colorization workflows.

Code-dump is an Objective C program that decompiles PPC Objective C programs on Mac OS X, relying on their inherently structured format.

iOS Hierarchy Viewer allows developers to debug their hierarchies for both UIView's and CoreData models. If there are problems with layout calculations, you can find them with ease by introspecting real-time preview of your views inside a browser. If your data is behaving weirdly, you can easily navigate through it via a browser. This tool predates commercial tools like Reveal and Spark Inspector, and it's available for free.