Keep the receipt, and give an expense a split of its own.
• Attach a photo to a transaction: a receipt, an invoice, a warranty. You both see it, and a camera on the row marks it.
• An expense can have its own split instead of the month's, like 100/0 for something that's yours alone. It's under "Who paid?".
• Bug fixes and small improvements.
Both came from your requests. Keep them coming.