Smartspender – designing a stylish app for tracking your spending habits
infinum.co
infinum.co
It strikes me that the part that makes expenses tracking hard isn't how pretty your app is, but forcing users to regularly and consistently enter expenses. I know that I've never managed to track expenses for more than a month before starting to slip and eventually giving up. What you need is a zero-effort workflow.
I think perhaps the ideal expenses tracking app would link into your bank details (via Yodlee or similar), perhaps use your location history to identify shops you went to, and then try and do as much heavy lifting as possible to give the user a very easy daily task of aportioning the cash they withdrew recently to the shops they visited.
That's debatable.