Generally, reading from the API is performed by executing a GET HTTP method to retrieve records/documents on your account.
Often a GET will return all records on the account as a list such as
GET /api/Forms - Return a list of all forms containing key attributes on the account visible to the logged in user.
Or the records by be filtered by one or more of the main attributes
/api/Forms/{id} - Return the Form Document by its unique identifier that includes all the form field attributes and full list of attributes
In some cases the records to retrieve may be limited by more than unique id and may take query string parameters
/api/Forms/{Id}/completedrecords/{rowId}/reports?ReportId=12&ReportFormat=1 - return a BLOB object form formid (id) for the data row (rowId), utilising report id (reportId) in the default format (PDF)
The API gives access to all the ids required to create requests.
For example a list of reports defined against a form can be returned with
/api/Forms/{id}/reports
The list of report formats supported can be queried by querying the the optional ReportFormat query string parameter
As a note the core objects within WorkMobile return full lists of things. So you get a full list of Forms, User Groups and Mobile users. There is no paging on these items. The lists return a subset of attributes and even on some of the larger clients Mobile Users and Forms rarely exceed several thousand items especially when organised into user groups or multiple departmental accounts