Coinciding with the announcement of Android 4.1 Jelly Bean, Android developers can now pull down a new revision of Android's SDK tools – revision 20, along with a new version of the ADT Plugin, also r20 (which Eclipse users will need to use SDK r20).

The revised SDK tools bring several improvements. One of the notable additions to the SDK tools is System Trace (otherwise known as systrace), a tool (included in Project Butter) that helps monitor system activities, allowing developers to pinpoint graphical rendering or other issues. For those wondering just what else is new, take it from the revision notes found at Android's Developer site:
General notes:
- Added new Device Monitor application, grouping Android debugging tools into a single application, including ddms, traceview, hierarchyviewer and Tracer for GLES.
Read More