Take a photo of a receipt with your phone

Open the client's Overview. Next to Upload document you find Take photo. Owners, admins, accountants, bookkeepers and client contributors see it; the read-only roles do not, and a client must be open.
Tap Take photo. On a phone the rear camera opens; take the picture and confirm it. The photo goes straight to the client as a document, marked as coming from a phone. Each tap sends one photo, so tap again for the next receipt. On a computer the button only opens the normal file picker for images.
The server accepts JPEG, PNG, WEBP, TIFF and PDF, not HEIC. A browser such as Safari converts an iPhone HEIC photo to JPEG itself. If yours cannot, the app says This browser cannot convert HEIC photos. Set the camera to JPEG (Most Compatible) or upload a JPEG. Change the camera format to Most Compatible in the phone's camera settings and take the photo again.
Wait until the upload has finished: leaving the page while it runs asks for confirmation. The button shows no "uploaded" message, unlike Upload document. If it fails you see The photo could not be uploaded. Try again; the usual upload limits apply (a file over 20 MB, an empty file, the same file twice, too many uploads in a minute), but this button only shows the general message.
Afterwards the photo is an ordinary document: the agent reads it, you find it under Bookings in the view Documents, and you review it in the Inbox.
You can put the app on the home screen of your phone: the app can be installed from the browser's own menu (Add to Home Screen on an iPhone, Install app or Add to Home screen on Android). It then opens full screen like an app, so Take photo is a tap away. The app itself shows no install prompt, and it is not an app from an app store.