Firefox will stop updating the Aurora Channel app for Android on April 18th, which is tomorrow, stating that it was simply not meeting their expectations as a base channel for the most experimental features when new releases were pushed out to users and developers. Going forward Firefox will be using Nightly builds for experimental features. This should sound familiar to most custom firmware developers and those who like to flash custom ROMs as nightly builds are commonly used for quick and more incremental updates while trying to keep things as current as possible. Nightlies also tend to include new features for testing, and this is what Firefox will be doing here for their pre-release software.
Mozilla's Aurora Channel release app which was in an unreleased status didn't have a very long shelf life, having only launched on the Play Store last fall but more specifically at the end of September That being said Aurora has been available for a lot longer than since just last Fall, this merely marked the time when Firefox decided to make it available as an official Play Store download. That being said, it makes sense that the Firefox team would want to drop development on it if it wasn't serving the purpose that they had hoped it would. In addition to the Nightly builds for the experimental features, Firefox Developer and Firefox Beta channels will be geared more towards stable releases and will be the closest users can get to an actual stable release of the Firefox browser app. Users can think of this like Google's Chrome Dev and Chrome Beta Android app versions.
Firefox explains that these changes will pose some significant benefits for users and developers alike. Although the Aurora channel will stop getting updates which will eventually make it obsolete, Firefox notes that developers will now be getting a higher quality for the other builds they're working with, which should lead to a shorter time frame for release cycles for platform features which in turn should lead to faster releases for the stable builds. When it comes down to it the Firefox team feels that they don't need the additional time of running new and experimental features through the Aurora Channel before moving on.