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UI Browser icon UI Browser 3.0.2 - A utility for exploring Apple's Accessibility API, and the ultimate assistant for GUI Scripting with AppleScript. UI Browser 3 requires macOS Sierra 10.12 or later and supports all releases through macOS Monterey 12. It is a Universal app. It runs natively on an Apple silicon Mac during the trial period and with a Paddle registration key. It requires Rosetta translation to run on an Apple silicon Mac with a UI Browser 2 eSellerate key.

UI Browser End of Life: UI Browser will reach its end of life and be retired on October 17, 2022. The current release of UI Browser, version 3.0.2, will not be updated. On the end-of-life retirement date, the PFiddlesoft website will be closed. Thereafter, product support will no longer be available. I am currently making arrangements for a permanent download site for the version 3.0.2 disk image for licensed users and for public access to the source code. UI Browser has been a labor of love for me, its sole developer for almost twenty years. Now that I am 79 years old, it is time to bring this good work to a conclusion. Bill Cheeseman, April 17, 2022.
framework icon PFiddlesoft Frameworks - Cocoa frameworks for macOS that support and enhance Apple's Accessibility and Quartz Event Taps APIs. PFAssistive Framework version 3.9.0 and PFEventTaps Framework version 1.6.0 require Mac OS X 10.7 (Lion) or later and support Accessibility features introduced through macOS Monterey 12.
Accessibility Testbench icon Accessibility Testbench - A free developer utility demonstrating how to grant access to the computer using the Accessibility security features introduced in OS X Mavericks 10.9. Version 1.0.8 requires OS X Mavericks 10.9 or later and supports all releases through macOS Monterey 12.
Event Taps Testbench icon Event Taps Testbench - A free developer utility for exploring Apple's Quartz Event Taps API. Version 1.4.0 requires Mac OS X 10.7 (Lion) or later and supports all releases through macOS Monterey 12.
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Go to UI Browser Downloads to download UI Browser, review its licensing terms, and purchase a registration key. Send licensing questions to

Go to PFiddlesoft Frameworks Downloads to download the frameworks. They are free for personal use or for use with your free software products. They may no longer be licensed for use with commercial applications

Accessibility Testbench and Event Taps Testbench are free, and their source code is also freely available.

For technical support for any of our products, go to its Product page and click the Support button. Send support questions to

Security Policy:

All of PFiddlesoft's applications are signed with our Apple Developer ID for increased security, and UI Browser is notarized by Apple to assure users that it is from a trusted developer and was scanned for malicious code by Apple to ensure its security. If an application has been altered since we posted it for download here, Gatekeeper will prevent it from running after you install it. The latest distribution disk images are also signed with our Developer ID.

Mac App Store Policy:

PFiddlesoft's products are not sold on Apple's Mac App Store. Our products are developer utilities and assistive applications for Mac users with disabilities, and they employ Apple's Accessibility and Quartz Event Taps technologies to help users control other applications and system features. Third-party products that use these technologies are not eligible for the Mac App Store.

About PFiddlesoft™

PFiddlesoft™ is the name under which PreForm Assistive Technologies, LLC distributes software for Macintosh computers with an emphasis on assistive technologies. Some of these products were formerly distributed by PreFab Software, Inc.

PFiddlesoft has unmatched experience controlling the graphical user interface of applications running on Apple computers using AppleScript and other technologies. Our products carry on the tradition of PreFab Player, a seminal product released in 1994 for the classic Mac OS. Now, PFiddlesoft brings our expertise to you on macOS with several established products and the frameworks on which they are based.

UI Browser was first released in 2003 to support Apple's Accessibility and GUI Scripting technologies. Read about it and download a fully functional 30-day free trial version at UI Browser. The PFiddlesoft Frameworks come with extensive documentation, including a programming guide and technical references. Event Taps Testbench was released in 2007, and Accessibility Testbench was released in 2013. Both applications are available for free with source code.

All of PFiddlesoft's products are written and maintained by Bill Cheeseman. He has been well known for many years in the AppleScript community as originator in 1996 and long-time Webmaster of The AppleScript Sourcebook website. He is the co-author with Sal Soghoian, Apple's former product manager for AppleScript and automation technologies, of a popular book about AppleScript, Apple Training Series: AppleScript 1-2-3 (Peachpit Press, 2009). In 1999, he pioneered the original Vermont Recipes website where many current Cocoa developers learned their craft with the Developer Preview version of Mac OS X, and he has since written the 2003 first edition and the all-new 2010 second edition of a book about writing Cocoa applications for Mac OS X, Cocoa Recipes for Mac OS X: The Vermont Recipes (Peachpit Press, 2010).