I use Prosper Daily (formerly Billguard). They take an inbox-zero style approach to tracking finances, pulling in your bank and credit card spending. The simple analytics make it easy to understand what your spending is this month relative to the last, and then easily let you breakdown your purchases by category and track this month over month. I've found that their categorization is the most accurate and simple to setup, and have felt a bit overwhelmed when trying this with other apps. At this point I think I've tried at least a dozen other spend tracking apps, and I keep coming back to this one.