We've asked Google for comment on the move.

The company is already quite clear about the rationale, however. Vendors officially need to get certification to load Google apps (Android's licensing model is built around this), but some of them ignore this requirement and either load the apps regardless or encourage you to download them yourself. This new block theoretically pushes those less-than-scrupulous brands to clean up their acts by either obtaining certification or sticking to an AOSP version of Android, where they'd depend on third-party apps.

The problem, of course, is that it leaves custom ROM users caught in the crossfire. They may have to be more selective about when they install ROMs and skip minor updates. It's far from the end of custom firmware, but the era of anything-goes firmware (on phones that allowed custom ROMs in the first place, that is) might be winding down.