Thanks for the suggestion! We do have a feature like this on our website (“itemized bills”), but unfortunately we don’t have any plans to add that feature on mobile right now. We’ve tried designing it, but it always feels like way too much work to add tons of individual items on a mobile device, where there’s less space onscreen and typing is more difficult. For now, your best solution on mobile is probably to include information about the items that you split in the expense notes, or to attach a picture of the receipt to the expense. Apologies for the inconvenience!