Ability to add and subtract right from the input field, and sanitize number formats.

Currently in Lunch Money, I find it's quite easy to have it mess up inputs. If you are copying and pasting from another application, it can often contain decorations such as $4,000.00 which will break in Lunch Money. Having a simple sanitation process would benefit adding transactions a lot, especially if your on a phone.

This includes quick addition, subtraction, multiplication and division.

For example, when splitting a transaction to multiple categories, you can see that there is a remainder of $1.48. It would be nice to go into the second category and have the ability to just specify +1.48 to the input which would add to the existing amount already there, instead of having to adjust and round manually.