For an app developer, there's nothing worse than finding out your latest update is catastrophically flawed and blowing up for your users. This is the reason Google introduced the alpha and beta channels, and then added staged rollouts. These features give developers a way to steadily release new versions into the wild, discover their bugs, and fix them before a wide release. However, all of this still relies on treating some of your users as guinea pigs. If you'd like to keep them around, it's best to minimize the fallout of a bad release as soon as it's discovered. To make things a little easier, Google has added a new button to the Developer Console that stops a staged rollout immediately.
The button is labeled "Halt staged rollout," and it can be found under the Production tab for each APK. This only works on releases that are on staged rollouts, so this won't be an option once an app goes into wide release. Once activated, the Play Store will cease distribution of the staged release – new and existing users will only have access to the previous release.
Halting an update won't do anything for devices that have already installed the faulty apk. If the issue is critical and a fix can't be written quickly, the best strategy may be to re-upload an old version with a new version code.
Once the issues have been ironed out, developers are able to resume distribution of the halted apk, or replace it with a newer version that immediately becomes available to the same users that received the bad release.
No developer ever wants to back out of a release, but if it ever becomes necessary, it can be a real life-saver. The ability to halt an update mid-release is all about damage control, and it's about the fastest solution available. It's great that Google is giving developers another way to keep their customers happy, or at least keep the number of unhappy customers to a minimum.
- Google Play Support