FLEX

FLEX (Flipboard Explorer) is a set of in-app debugging and exploration tools for iOS development.

Feature Overview

Inspect and modify views in the hierarchy.
See the properties and ivars on any object.
Dynamically modify many properties and ivars.
Dynamically call instance and class methods.
Access any live object via a scan of the heap.
View the file system within your app's sandbox.
Explore all classes in your app and linked systems frameworks (public and private).
Quick access to useful singletons such as [UIApplication sharedApplication], the app delegate, the root view controller on the key window, and more.
Dynamically view and modify NSUserDefaults values.

FLEX builds on ideas and inspiration from open source tools that came before it. The following resources have been particularly helpful:

DCIntrospect: view hierarchy debugging for the iOS simulator.
PonyDebugger: network, core data, and view hierarchy debugging using the Chrome Developer Tools interface.
Mike Ash: well written, informative blog posts on all things obj-c and more. The links below were very useful for this project:
RHObjectiveBeagle: a tool for scanning the heap for live objects. It should be noted that the source code of RHObjectiveBeagle was not consulted due to licensing concerns.
heap_find.cpp: an example of enumerating malloc blocks for finding objects on the heap.
Gist from @samdmarshall: another example of enumerating malloc blocks.
Non-pointer isa: an explanation of changes to the isa field on iOS for ARM64 and mention of the useful objc_debug_isa_class_mask variable.

Search bar filtering in file browser
Sorting by file size in file browser
File browser: try to parse binary files as plists or keyed archives even if they lack the extension?
Demo app
Swift runtime introspection (swift classes, swift objects on the heap, etc.)
Layer hierarchy support
Add new NSUserDefault key/value pairs on the fly