With Inbox by Gmail saying goodnight in March 2019, some of us will be looking for a new experimental email client. Sadly, one potential replacement will no longer be an option: Astro is being acquired by Slack and will cease to operate as a standalone app on October 10.

New user signups have been disabled and the apps for Android, iOS, and Mac will stop working next month, with Amazon Alexa support and the current Slack integration also being killed. Whether you're a Gmail or Outlook user, you'll have to go back to the native app for your account, and be sure to check in on anything you've snoozed or scheduled in Astro before it shuts down — after October 10 you won't be able to access those any longer.

It's a sad day for anyone who's used Astro since it launched in 2015, but probably good news for Slack users. The company intends to leverage the expertise of the Astro team to improve interoperability of Slack channels and the more traditional form of communication that is email.