I like that it's easy to use & understand what all fields are used in an invoice (for example) without having to look up each one individually.
The interface could be made easier to read with more contrast between different elements - even if they have similar sizes or colors. We're using this application as part of our internal reporting process so we don't need any assistance from them directly. It has been helpful being able to see at-a-glance how much mileage was driven by specific vehicles during their trips compared against invoices submitted.