Systems and methods for managing communication between applications (e.g., apps) in a host computing environment. Apps are published to a globally-accessible site. Upon download of an app to a host computing environment, apps can register themselves with a communication gateway as being discoverable and permissive to inter-app communications. Message queues are created to facilitate asynchronous communications between apps. After registration, any of the apps can send and receive messages using the communication gateway. The messages can be directed to any other app that is registered with the communication gateway. Using the message queues, the communication gateway facilitates asynchronous app interactions such that any app can communicate with any other discoverable and permissive app. Aspects of operation, discoverability and other attributes can be codified in an application manifest that is processed by the communication gateway. Discoverability, source of origination, payload contents, permissions and other attributes are carried in the application manifest.