Google manages ADT development, as well as the standard Android platform. However,

the two products are managed very differently, particularly in regards to the open-
source nature of the products. The ADT project is developed by a different group from

the one that manages the main platform. The tools are released separately from the
standard SDK and follow their own release cycle, which is frequently (but not always)
tied to the platform release.
The standard OS is developed behind closed doors—contributions are not accepted to
the current code base. The source code is released to the public at some point after the
group releases it to manufacturers and other insiders.
The first line on the ADT website makes it clear that this project is different. It reads:
“The Developer Tools for Android are being developed entirely in the open and [the
project] is accepting contributions.” ADT is developed as a series of open source projects
with publicly accessible Git repositories and a public bug tracker. The management
group solicits contributions from the community and considers them for implemen‐
tation in current releases. You can find information on how to contribute on their