Google is living up to its word and posting warning labels for battery-killing apps. 9to5Google spotted Google’s rollout announcement, which the company previously said would arrive on March 1.

The label says, “This app may use more battery than expected due to high background activity.” If you don’t yet see the warnings, they may not have reached you yet. Google says the banners will “roll out gradually to impacted apps” in the coming weeks.

Warning labels aren’t the only stick in Google’s fight against infringing apps. They may also be excluded from discovery services like Play Store recommendations.

Google’s definition of battery-draining apps centers around Android’s “partial wake lock” mechanism. This service allows an app to keep the phone’s processor running even while the screen is off. There are logical exceptions where apps do need this: audio playback, location access, etc. But the company apparently sees too many abusing that API for other reasons. And Google wouldn’t want people to assume the problem is with the hardware and switch to an iPhone — because then we’re talking about money.

If you’re a developer, Google’s technical documentation offers much more detail. For everyone else, keep an eye out for those Play Store labels and consider steering clear of those apps until their devs clean things up.