That is really a question for the BOINC developers, not WCG.

As for the sciences, unless there were a very significant number of machines with ARM processors willing to participate in WCG, I wouldn't count on them being available for ARM.

Somewhere, someone commented Android was not secure enough, therefor going for Linux for ARM. BOINC is ultra secure, that is, as long as you don't hook the client up to the Phish-app project from Hackistan. Of course, with some 'private' builds of open source coded BOINC floating around to include on torrents, you only get the client from WCG or Berkeley and nowhere else.