You can upload receipts (in image or pdf format) in both your Starling mobile app and in Online Banking. No matter where you upload the receipt, you will still be able to view it in the Bookkeeping section of the Toolkit.
In your mobile app, go to the transaction feed (list), tap on the transaction, which will display the transaction details. Here you will be able to add attachments of receipts.
In Online Banking, you can upload receipts in the home feed or in the Bookkeeping section of the Toolkit. Just click on the transaction for which you want to add a receipt. This will open a sidebar with the details for that transaction, where you can upload receipts, invoices and other attachments.