Two apps can share data by simply configuring each app to use a common data source (such as a worksheet). But one app cannot display views of another app, nor invoke actions configured in another app. You can navigate between apps, but doing so effectively closes the app you start from and opens the app you’re going to, with the associated delays.
A common approach to app building is to have a simple app used by field staff to collect data, and a second used by office staff to analyze the data. In this model, the two apps share one or more tables that store the collected data. Each app may have non-shared tables needed for functions specific to each app.