When you’re a developer, you’re faced with a whole host of challenges and concerns based around who you want to develop things for. You have to figure out what audience is best for an app or site as well as decided to pick which platform to build it for. Luckily, there are technologies out there that will help you build things that can build thing for multiple devices and browsers, and Yahoo! is releasing a framework to the open source community to assist in that goal today.

The framework, Mojito, is a “JavaScript-centric presentation platform for connected devices”, built by Yahoo! developers to bring content to customers no matter what platform or device they’re on.

Here’s how Yahoo! explains Mojito:

If you want to build apps that reach all your customers, anywhere and everywhere, this might ring a bell. Today you have to make hard choices, mutex choices – I hate those. Build a desktop Web site? Build a mobile Web site? Build an app? Translation: an iOS app? Or an Android app?

Mmmmh. Must I pick one?

Here’s an idea: build a standards-based application, and tailor it to the device it runs on. Make it degrade nicely, on all the devices. Easier said than done, for sure, but having a solid framework in place helps a lot. That’s Mojito (and YUI3). We’ve been working with Mojito for a while internally, building hybrid apps like Yahoo! Livestand. Or Fantasy Finance, a Web site. Or Fantasy Premier League Football, a mobile Web app. All three are built using Mojito because it lets you develop one codebase for any type of device. Think of the reduced effort!

By having one codebase from which to work, the need to have multiple developers stepping over one another to port versions of your app to say, Android, is not a problem any longer.

Letting this framework go into the wild for developers is an extremely smart move by Yahoo! as more companies are starting to give back to the community to build their brand and remain relevant. While developers might not use Yahoo! products specifically, being able to identify the company with a tool that can save them a good bit of time is a way to create goodwill and remain a part of the ecosystem.

In addition to making Mojito available for use, Yahoo! is hoping that the developer community can take the framework to the next level by adding its own nuances and features. This of course is also a great thing for Yahoo! in that it gains access to fresh new ideas and developers without having to pay for it.

➤ Mojito on GitHub

You can view it in its full glory here, and marvel at the zero image, 3,395 lines of CSS and 335 lines of Javascript version of the iPhone 4.

You can even click the home button, slide to unlock it, and shut it off with the power button.

The fact that all of the features of the phone and design of the icons were done without use of images is astonishing, and impressive. Well done!

While Mozilla was promising to release version 9 of its Firefox browser tomorrow, the official download links are live now.

Huge performance changes have been made in this release, while there aren’t any user interface changes that you’ll notice.

The double-digit increases in performance that most are reporting come from a new feature called “type inference”, created by Mozilla developer Brian Hackett. The feature now quickly chooses how to handle JavaScript, which doesn’t require a developer to define a variable. That makes the browser work overtime, but with type inference, the difference in performance is definitely noticeable.

Here are the rest of the changes and updates that come with version 9 of Firefox:

Added Type Inference, significantly improving JavaScript performance
Improved theme integration for Mac OS X Lion
Added two finger swipe navigation for Mac OS X Lion
Added support for querying Do Not Track status via JavaScript
Added support for font-stretch
Improved support for text-overflow
Improved standards support for HTML5, MathML, and CSS
Fixed several stability issues

You can download Firefox 9 for Mac, Windows, and Linux now.

On Friday, I wrote about Mozilla’s Firefox Challenge for charity. The idea is simple; 12 celebs, 12 causes, and the one who raises the most money by January 11th, 2012 gets an additional $25,000 from Mozilla for its charity.

“Which celeb will win?” was the question a few folks have had. Well, we might have our answer before the competition is over. It’s not a celebrity that’s in the lead, it’s a group of geeks calling themselves #TeamJS. JS standing for “JavaScript”, of course. Mozilla allowed anyone to create a team to compete with celebs like Seth Rogan, Jonah Hill, and Sophia Bush.

Out of nowhere, #TeamJS has raised over $12,000 for its charity, “Feeding America“.

At the helm is O’Reilly tech writer, David Flanagan. In a post called “Geeks vs. Celebs“, Flanagan calls on his geeky pals to help raise enough money to win the $25k prize in January for Feeding America.

Here’s what Flanagan had to say about his rally for social good:

I want to challenge the JavaScript community, and the web developer community, and heck, the whole geek community to go head to head with the celebrities and raise more money than they can. So I’ve formed TeamJS to compete against the celebs in the challenge. We don’t get the head start of $5k seed money, but we can still win the $25K prize!

While everyone wins during this challenge, especially the charities, this is an interesting narrative to the social good movement on the web. No big names are needed to raise money, just passionate people with big hearts. Geeks have a voice too, and can obviously move crowds in a big way. See the tally below from the team’s Crowdrise page:

I’d love to see celebs like Jason Bateman and Will Ferrell pick up the pace as we enter the holidays. Putting a celebrity name in front of a charity alone doesn’t make the true difference, the passion has to be there too. Get involved by giving money to your charity of choice, and be sure to share your good deed on Twitter and Facebook.

Will the geeks reign supreme? We’ll be watching!

➤ Mozilla Firefox Challenge