Comparison of widget engines

This is a comparison of widget engines. This article is not about widget toolkits that are used in computer programming to build graphical user interfaces.

General

Engine	Creator	Current Version	License	Status
Adobe AIR	Adobe Systems	1.5	Proprietary	Discontinued
AveDesk	Andreas Verhoeven	1.3	Proprietary	Abandoned
Dashboard	Apple Inc.	1.8 (July 20, 2011; 13 years ago (2011-07-20)) [±]	Proprietary	Retired
DesktopX	Stardock	3.5	Proprietary	Abandoned
gDesklets	Martin Grimme and Christian Meyer	0.36	GPL	Abandoned
Google Desktop Gadgets	Google	5.0.0701.18382	Proprietary	Discontinued
Kapsules	Andrew Powell	0.9.9	Proprietary	Abandoned
KlipFolio	Serence	5.0D	Proprietary	Active and supported
Microsoft Gadgets	Microsoft	?	Proprietary	Discontinued
NetFront	Access Co. Ltd.	4.2	Proprietary	Discontinued
Netvibes	Netvibes	1.0	Proprietary	Active and supported
Opera	Opera Software	100.0.4815.21 (June 20, 2023; 2 years ago (2023-06-20)[1][2][3])	Proprietary	Discontinued
Plasma	KDE (Aaron Seigo, main developer)	4.14.3 (November 11, 2014; 10 years ago (2014-11-11)) [±][4]	GPL	Active and Supported
Rainmeter	Kimmo 'Rainy' Pekkola	4.3.1 - r3321 (September 22, 2019; 5 years ago (2019-09-22)) [±]	GPL	Active and Supported
Screenlets	Rico Pfaus (AKA RYX)	0.1.5	GPL	Abandoned
Serious Samurize	Gustaf & Oscar Lundh	1.64	Proprietary	Abandoned
SuperKaramba	Hans Karlsson	0.39	GPL	Abandoned
WebKit	Apple Inc.	?	BSD+LGPL	Active and supported
WidSets	Nokia	?	Proprietary	Discontinued
Yahoo! Widgets	Ed Voas, Michael Galloway, and Sam Magnuson [Note 1]	4.5.2	Proprietary	Discontinued
Engine	Creator	Current Version	License	Status

1. The Yahoo! Widgets was originally released by Arlo Rose and Ed Voas as Konfabulator. The name was changed several months after Yahoo! acquired the software in July 2005.

Operating system support

Engine	Mac OS X	Windows NT5 (XP)	Windows NT6 (Vista, 7/8/10+)	Linux	Android
Adobe AIR	Yes	Yes	Yes	Yes	?
AveDesk	No	Yes	Yes	No	?
Dashboard	Yes[Note 1]	No	No	No	?
DesktopX	No	Yes	Yes	No	?
gDesklets	No[Note 2]	No[Note 2]	No[Note 2]	Yes	?
Google Desktop Gadgets	Yes	Yes	Yes	Yes	?
Kapsules	No	Yes	?	No	?
KlipFolio	No	Yes	Yes	No	?
Microsoft Gadgets	No	No	Yes	No	?
NetFront	No[Note 3]	No[Note 3]	No[Note 3]	No[Note 3]	?
Netvibes	Dashboard bridge	Using browser	Using browser	Using browser	?
Opera	Yes	Yes	Yes	Yes	?
Plasma	Yes	Yes	Yes	Yes	No
Rainmeter	No	No	Yes	No	No
Screenlets	No	No	No	Yes	?
Serious Samurize	No	Yes	Yes[Note 4]	No	?
SuperKaramba	No	No	No	Yes	?
WebKit	?	?	?	?	?
WidSets	No[Note 5]	No[Note 5]	No[Note 5]	No[Note 5]	?
Yahoo! Widgets	No	Yes	Yes	No	No
Engine	Mac OS X	Windows XP (NT5)	Windows (NT6) Vista+	Linux	Android

1. As of El Kapitain the Apple dashboard is no longer enabled by default.
2. As for the next major version the gDesklets' developers are planning to support Windows XP and Mac OS X.
3. NetFront is a Mobile browser, which is also preinstalled on the PSP, and on the PlayStation 3.
4. The current version of Samurize (1.64.2) runs on Vista but there are a few minor issues that need to be worked out, such as security dialog prompts.
5. WidSets is for mobiles and runs on the Java MIDP 2.0 platform

Technical

Languages

Which programming languages the engines support. Most engines rely upon interpreted languages.

Engine	HTML	XHTML	CSS	XML	JavaScript	Perl	Python	Ruby	C++	Executable	VBScript
Adobe AIR[Note 1]	Yes	Yes	Yes	Yes	Yes	?	?	?	?	?	?
AveDesk[Note 2]	No	No	Yes	Yes	Yes	No	No	No	Yes	?	?
Dashboard	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes[Note 3]	Yes[Note 3]	?
DesktopX	Yes	Yes	Yes	Yes	Yes	Yes	Yes	?	Yes	Yes	?
gDesklets	No	No	No	Yes	No	No	Yes	No	No	No	?
Google Desktop Gadgets	?	?	?	Yes	Yes	No	No	No	No	Yes	?
Kapsules[Note 4]	?	?	?	?	No	Yes	Yes	No	?	?	Yes
KlipFolio	No	No	Yes[Note 5]	Yes	Yes	No	No	No	No	No	?
Microsoft Gadgets	Yes	No	Yes	Yes	Yes	No	Yes	Yes	Yes (as ActiveX)	Yes	Yes
NetFront[Note 6]	Yes	Yes	Yes	Yes	Yes	No	No	No	No	No	?
Netvibes	Yes	Yes	Yes	Yes	Yes	No	No	No	No	No	?
Opera[Note 6]	Yes	Yes	Yes	Yes	Yes	No	No	No	No	No	?
Plasma	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	?	?
Rainmeter	No	No	No	No	No	No	No	No	No	No	No
Screenlets	Yes	Yes	Yes	?	No	No	Yes	No	?	?	?
Serious Samurize[Note 4][Note 7]	No	No	No	No	Yes	Yes	Yes	Yes	Yes	Yes	Yes
SuperKaramba	?	?	Yes	Yes	Yes	No	Yes	Yes	Yes	?	?
WebKit	Yes	Yes	Yes	Yes	Yes	No	No	No	Yes	?	?
WidSets	?	?	?	?	?	?	?	?	?	?	?
Yahoo! Widgets[Note 8]	Yes	Yes	Yes	Yes	Yes	No	No	No	No	No[Note 9]	No
Engine	HTML	XHTML	CSS	XML	JavaScript	Perl	Python	Ruby	C++	Executable	VBScript

1. Widgets for Adobe Air can also be programmed in Adobe Flash, and Actionscript.
2. AveDesk can be extended using AveScripter, which supports plugins written with XML and Javascript, extended using CSS.
3. Dashboard uses a technology called Cocoa Plugins.This allows for Objective-C code to be used through the plugin. The plugin is written with Cocoa and is compiled.
4. Widgets for Kapsules and Serious Samurize can be written in any scripting language for which there is an ActiveScript engine, including PHP, JScript, VBScript and Ruby.
5. KlipFolio supports custom styles using CSS syntax.
6. This is only relevant for Opera's and NetFront's extensions; the web browsers themselves support HTML, CSS and others.
7. Samurize supports DLLs compiled with C++, Delphi, PowerBASIC, and FreeBasic, among others. HTML/XML/CSS support can be added by using certain plugins.
8. Yahoo! Widget Engine supports Perl and Python indirectly through the use of the shell, provided that the interpreters are installed on the machine (on Mac OS X, they are by default).
9. Yahoo! Widgets can interface with COM (windows) or AppleScript (Mac OS)

Formats and Development

Engine	IDE	Widget Container	Widget MIME Type
Adobe AIR	Flex Builder 3, Flash CS4, Dreamweaver CS4	ZIP	application/vnd.adobe.air-application-installer-package+zip
AveDesk	AveScripter	ZIP	?
Dashboard	Dashcode	ZIP	application/x-macbinary
DesktopX	Desktop X Pro	EXE	?
gDesklets	No	Tar.gz	?
Google Desktop Gadgets	Google Desktop Gadget Designer	ZIP	app/gg
Kapsules	?	ZIP	?
KlipFolio	No	Proprietary XML Format	?
Microsoft Gadgets	No[Note 1]	ZIP	application/x-windows-gadget
NetFront	No	ZIP	application/x-opera-widgets
Netvibes	No	Online	?
Opera	Opera Dragonfly	ZIP	application/x-opera-widgets
Plasma	No	ZIP, with plasmoid as extension instead of zip	?
Rainmeter	No	ZIP, with rmskin as extension instead of zip	application/vnd.rainmeter.SkinInstaller
Screenlets	No	Tar.gz	?
Serious Samurize	Serious Samurize Config Editor	ZIP	?
SuperKaramba	No	Tar.gz	?
WebKit	No	?	?
WidSets	?	?	?
Yahoo! Widgets	No[Note 2]	Proprietary Format, ZIP	application/vnd.yahoo.Widget
Engine	IDE	Widget Container	Widget MIME Type

1. Microsoft Gadget have documentation, but no IDE to aid development.
2. Yahoo! Widgets have documentation, but no IDE to aid development. A script was provided to allow Photoshop to be used as the Graphical Designer, the script created a widget whose objects were based upon photoshop layer sets or groups

Development Tools

As widgets are largely combinations of HTML or XHTML, CSS, and Javascript in most cases, standard AJAX tools, such as Eclipse ATF, can be used for development. Specialized tools may give access to additional capabilities supplied by frameworks such as Dojo or Openrico.