If the approval flow is activated for your account approvers and/or controllers will be assigned to expenses. When submitting an expense, it is sent to the approver. If a second level of validation is configured for your organization, a controller will need to perform a second level of validation.
Approvers and Controllers are defined on an expense level. The Approver/Controller of each expense is indicated in the history of an expense.
The history of an expense can be found via the web application. First allocate the specific expense in the "Expenses" tab and then click on an expense to see the details. Then, on the left, click the "History" tab.
When reviewing this, you will be able to find the Approver/Controller on the right side:
The Approvers and Controllers of an expense are assigned by the Administrator of your account.