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All you need to do is make sure that the case type is the same.
Example 1: Multiple applications without case sharing
A project may have two applications that are not explicitly related to each other or connected. For example, a your project may have a set of Community Health Workers who specialize in malaria and a set that specialize in maternal health. You could have a separate application for each set of CHWs. You may want to keep these applications in the same project space so that the same mobile user can use either application, and so that all of the web users have the same access to data from both applications in one place.
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You would want to put applications in separate project spaces if you want to keep the data separate and accessible to different web users.
Example 2: Case sharing across multiple applications
Overview
Imagine a project where Community Health Workers visit pregnant women and register them in their CommCare app. Nurses at the clinic nearby want to have access to a women with pregnancy danger signs so that they can follow up with them and update their own CommCare app with additional information. This project could have two applications; one for Community Health Workers, and one for the Nurses at the clinic.
How to set it up
Application 1: CHW app
Application 2: Nurse app
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