Where can I find the source code for the gmail, facebook, and twitter apps for android? Are they even open source?
There are some components I need to use from these three 'supposedly' open source apps for android.
I looked at the source code for android, but I can't seem to find the gmail app; I can only find the email app.
I looked at the source code for the official facebook sdk for android, but there is no source code for the actual facebook app; there only is the source for the sdk, not the app.
And as for the twitter app, I can't even find the source code repository despite a million articles on the web saying that the twitter for android is open source.
Does anyone know where?
None of those apps are open-source as of November 2010, and I wouldn't hold out hope for any of them except the Twitter app (and even there, don't hold your breath). Here's why:
Facebook's client apps aren't open-source on any platforms that I know of, only their SDK is, and they've never made any claims that it would be, so I don't think there's any reason to expect it to ever be publicly available.
GMail, Maps, Talk, and the Market are part of the "Google Experience" apps that are the carrot Google uses to force carriers and manufacturers to make highly compatible Google-cobranded phones and not run off and break the system's ability to work with 3rd-party apps and services, so I'd also never expect those to go open-source (at least any more than I'd expect to see the entire source-code of the GMail web client pop up any time soon). In fact, they threaten/send C&D letters to companies and even ROM-makers that try to even distribute those apps in binary form without proper permission.
While you can't prove the nonexistence of something, the Twitter app's source hasn't been released to my knowledge as of 11/2010. They said in their I/O 2010 design presentation and the blog entry that accompanied it that it would be in the "next few weeks" and news outlets picked up on that and turned that into "it's open source," but there hasn't been a peep from them on that point since then. In fact, in the latest revisions of the Twitter app on the Market they seem to have also backpedaled and nuked a lot of the design elements they talked about in the IO presentations (quickaction popups are now iPhone-style in-row sliding actions, for example). Google eventually opensourced the 2010 IO schedule app, which has a lot of the same goodies (Dashboard, action bar, sync management), though.