“Expense reports are a special kind of hell. Employees are often stuck wondering when, if ever, they will get reimbursed. Managers and accountants, on the other hand, have to deal with extra paperwork and making sure that every meal, bar tab, and taxi fare was actually business-related. Y Combinator-backed startup Abacus wants to keep everyone from murdering each other with an app that ”kills the expense report” instead.”