CobraDroid is a custom build of the Android operating system geared specifically for application security analysts and for individuals dealing with mobile malware. There are currently two actively developed branches of CobraDroid: one based off Android 2.3.7_r1 ("CobraDroidGB"), and one based off Android 4.3.1_r1 ("CobraDroidJB"). Once all features are ported to CobraDroidJB, development of CobraDroidGB will be discontinued (except for bug fixes!).
Note that CobraDroid is not actively being maintained or developed at this point. If you would like to play with the source code, it can be found here. Maybe someday I'll pick the project up again!