When the approvals workflow is enabled, users with the Authorising Manager role may receive requests to review expenses claims from other users. You can read more about how this is works here. If you have the appropriate role, then when logged into the RIPA Expenses mobile app you'll see an "Approvals" section in the "Expenses" tab. If any claims are awaiting review, there will be a number shown next to the "Needs review" item. Tap on this to show the list of waiting claims:
Tapping on any claim in the list shows its details. At the bottom of the page are the buttons you can use to approve, decline or request changes to the claim.
If you request changes, the claimant is notified that they have an expense which needs their attention; when they view it, they'll see a message you wrote. First, tap on "Request changes". A type-in area appears above; type in the message that you want the claimant to see here. Now tap on "Request changes" again to finish reviewing the claim and notify the claimant.
There is a similar process for "Decline". You need to give a reason for refusing the claim, else it can be quite distressing for the claimant! Tap on the "Decline" button, enter a reason just as with "Request changes" above, then tap on "Decline" again.