To get the best results, it makes sense, upload the receipt to Bonsy right after you have received it at the cash register.
Since the receipt is probably the least wrinkled at that time, this is likely to give you the best result.
Make sure the lighting is correct and use the flash if necessary.
Even though the result is usually visible in the app after a few seconds, you don't necessarily have to wait for it. You can also simply upload the photo to Bonsy and Bonsy will inform you as soon as the categorization of the receipt is complete. To do so, please activate push notifications.