Jetpack is a project to make it easy to build Firefox 4 add-ons using common web technologies like HTML, JavaScript, and CSS. Our goal is to enable anyone who can build a web site to participate in making the Web a better place to work, communicate, and play.

Android is a software stack for mobile devices that includes an os, middleware and key applications. The Android SDK site provides the tools and APIs necessary to begin developing applications on the Android platform using the Java programming language.

Today we are releasing version 1.2.5 of the App Engine SDK for both Python and Java, our first simultaneous release across both runtimes. We're excited about the great new functionality in this release ... including XMPP!