No, you can only upload receipts from the mobile app.

After uploading, your receipts will be listed in the web app's Receipts Inbox. From the Receipt Inbox, you can manage your receipts and process them. You can either convert a receipt to a new transaction in the Expense Tracker or connect it to an existing transaction. The receipt table in the Receipt Inbox will track the status of all receipts, so you'll know which ones have been processed and which ones still need attention.