Microsoft announced on May 16, 2014 that they will be discontinuing support for Autohosted Apps in Office365. The change will be effective June 30, 2014.
What are Autohosted apps?
With SharePoint 2013, Microsoft introduced three new models for deploying customizations to SharePoint. These include SharePoint-hosted Apps, provider-hosted Apps, and Autohosted Apps. SharePoint-hosted Apps consist of client-side code and live directly within SharePoint. Provider-hosted apps are developed to live outside of SharePoint, but with nice SharePoint integration. Autohosted apps were intended to quickly deploy supporting SQL database and Application backend support directly into Microsoft Azure. The idea was to take away the need for you to provide (or host) your own infrastructure and instead quickly deploy what you need to Azure so you do not need to worry about the backend so much.
Why are Autohosted Apps going away?
While Autohosted Apps seemed very cool in theory and demoed well, they were not very realistic. Either they did were not robust enough to handle real application scenarios or the security model behind them just didn't translate well for real customers.
How do those using Autohosted Apps transition?
For those actually using Autohosted Apps, Microsoft has provided a strategy to transition from the Autohosted model the Provider hosted model.