If you looked at OilCan – a Greasemonkey-like browser extension for Android – and Mosembro, you’d quickly realize that they have a lot in common. Both are experimental browser extensions which run on Android, both aim to make websites friendlier, both support installable actions written in JavaScript, and both make it possible for those scripts to modify web pages and launch other applications. And since looking at OilCan’s source code has allowed me to avoid reinventing the wheel at several occasions, some pretty obvious similarities can also be spotted at the source code level.

So, with so many things in common, how are they different at all?

The main difference, I believe, is what causes user scripts to be triggered. A typical OilCan script is triggered by a web page’s URL and is executed only once. Its goal is to change the content or functionality of a very specific document. Mosembro scripts, on the other hand, are triggered by embedded microformats and can be executed dozens of times for each page, while not caring about which page they were executed on.

I could say at this point that OilCan’s approach to invoking scripts could be compared to function calls in programming languages and Mosembro’s approach compared to what is done in aspect oriented programming, with functionality implemented by actions attached to bits of semantic content being cross-cutting concerns, but I’m not sure about it, so I won’t. ;-)

Also, because Mosembro is very narrowly focused on adding functionality to web pages based on semantic data embedded in them it can also provide additional infrastructure, like microformat parsers and action menus, which wouldn’t exactly fit in with a more general purpose framework. And finally, there’s the integrated support for site-level search.

So, there you have it. While it’s true that both apps have a lot in common, it’s their unique features that really matter.

If you already have Mosembro installed, uninstall it first by running: adb uninstall com.lexandera.mosembro
The new version can then be installed by executing the following command: adb install mosembro-r2.apk

New features include:

• It is now possible to install addidional actions which extend Mosembro’s functionality.
• Addresses can be copied to clipboard.
• Improved security and various bugfixes.

Screenshots of new features:

Mosembro r5: dialogs for installing and managing installed actions

Several simple actions can be installed from the bottom of the demo page which is loaded when Mosembro starts up. Go & try them out.

Confused? Yes, many of us are. So here are two excellent articles that might clear things up a bit for you:

• Never Mind the Semantic Web by Glenn McDonald, on 13 reasons for confusion.
• Misconceptions about Semantic Web by Rod Petrovic, on how you are probably wrong. ;-)

If you already have Mosembro installed, uninstall it first by running: adb uninstall com.lexandera.mosembro
The new version can then be installed by executing the following command: adb install mosembro-r2.apk

Major changes from r1:

• Multiple actions can now be attached to a single link.
• Microformat parsing logic was separated from action logic. Each microformat is parsed only once now and parsed data is then passed to one or more actions registered to handle that microformat.
• Two new “travel to…” actions were added for addresses. One uses London Journey Planner and the other one uses Bay Area Trip Planner
• alert(), confirm() and prompt() JavaScript functions now work.

Here is an example screenshot of multiple actions on one link:

Multiple actions attached to one link

More screenshots and/or a video should be available in a couple of days.

Speaking of which…

I performed some major surgery on Mosembro’s internals this past weekend. Scripts don’t do their own parsing of microformats anymore; instead, there are now dedicated parsers for each of the supported microformats. These parsers then call any scripts which might be registered to handle that particular microformat. This gets us closer to being able to implement support for installing third party scripts. It will also make it possible to attach multiple actions to a single event/address/etc., as shown on this mock-up:

Considering how small the codebase of Mosembro is, this shouldn’t take long to implement. Expect a new release soon™.

Meanwhile, if you have any suggestions, I’d be more than happy to read them.

Mosembro, short for “mobile semantic browser”, is a proof-of-concept web browser for the Android mobile platform, which has integrated support for microformats. It was my entry for the Android developer challenge (but was called SmartBrowser back then), and while it wasn’t one of the 50 finalists who made it to the second round, it did finish in the top 25% of all entries, which is pretty good, I suppose.

The goal of this project is very simple: to make a better mobile browser with the help of embedded semantic metadata.

What does it do? It scans any loaded web page for microformats and inserts special links into it, based on any microformats it may have found. These links then enable the user to quickly perform tasks like looking up an address on a map or adding an event to his calendar. While manually performing these tasks is very simple on a computer, it can be pretty tedious on a mobile device without a proper keyboard, mouse, or even without the ability to copy and paste text.

Full feature list, demo videos, downloads and source code are available at the Mosembro project page.