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UI Browser icon UI Browser 2.7.0 - A utility for exploring Apple's Accessibility API, and the ultimate assistant for GUI Scripting with AppleScript. Version 2.7.0 requires Mac OS X 10.7 (Lion) or later and supports macOS High Sierra 10.13.
framework icon PFiddlesoft Frameworks - Cocoa frameworks for macOS that support and enhance Apple's Accessibility and Quartz Event Taps APIs. PFAssistive Framework version 3.8.0 and PFEventTaps Framework version 1.5.5 require Mac OS X 10.7 (Lion) or later and support Accessibility features introduced through macOS High Sierra 10.13.
Accessibility Testbench icon Accessibility Testbench - A free developer utility demonstrating how to grant access to the computer using the new Accessibility security features introduced in OS X Mavericks 10.9. Version 1.0.8 requires OS X Mavericks 10.9 or later and supports macOS High Sierra 10.13.
Event Taps Testbench icon Event Taps Testbench - A free developer utility for exploring Apple's Quartz Event Taps API. Version 1.3.9 requires Mac OS X 10.7 (Lion) or later and supports macOS High Sierra 10.13.
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To purchase a registration key for UI Browser, visit our eSellerate Web Store, or purchase a key online using the 30-day free trial version of UI Browser while connected to the Internet. You may have to make the purchase on a Mac running OS X Mavericks 10.9 or later. Visit UI Browser Downloads for details. Send licensing questions to

To license the PFiddlesoft Frameworks and review their licensing terms and disclaimers, visit PFiddlesoft Frameworks Downloads. The license is free for personal use or for use with your free products. We charge a flat one-time license fee for use of each framework with a commercial or other paid product line. Source code is available for a separate fee. Send licensing questions to

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

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

Join the UI Browser Users Group on Yahoo Groups to participate in ongoing discussion of GUI Scripting on macOS using the UI Browser application.

Security Policy:

All of PFiddlesoft's products are signed with our Apple Developer ID for increased security using Gatekeeper under OS X Mountain Lion 10.8 and newer. For the best experience running our applications with Gatekeeper, select the default setting, "Mac App Store and identified developers", in the Security & Privacy pane of System Preferences. If an application has been altered since we posted it for download here, Gatekeeper will prevent it from running without your permission after you install it. The latest distribution disk images are also signed with our Developer ID.

If you prefer the "Mac App Store" Security & Privacy setting, you can still run our products by choosing Open in the Finder's File menu or a contextual menu. You will have to authenticate with your password the first time. After that, you can run them by double-clicking as usual.

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.

If Apple changes the Mac App Store requirements in the future, we will consider whether to distribute products with the same or similar features on the Mac App Store. If we do, they may require payment of the full Mac App Store purchase price even if you already own a version purchased here on the PFiddlesoft site. We will continue to support every product that you purchase here for a reasonable time, but the features and prices of any Mac App Store products and updates we offer may differ from the features and prices of our products and updates available here.

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 by visiting UI Browser. The PFiddlesoft Frameworks come with extensive documentation, including a programming guide and technical references, and source code is available for a separate fee. Event Taps Testbench was released in 2007 and Accessibility Testbench was released in 2013, and both are available for free with source code.

All of PFiddlesoft's products are written and maintained by Bill Cheeseman of Quechee Software. 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).