Xero

The UI for entering time is tedious and creates too much friction. There's no evidence of usability testing having been done. Dates never include the day of the week—the main thing a real user is interested in. Even when there's only one "task", you must enter it again and again for every single time entry. There's no way to enter hours for the different days of a week together—you must laboriously create a new time entry individually for each day, and manually fill out each field using the MOUSE! (Keyboard support exists but is not smooth.) The API support is non-existent unless you have admin-level access to the organization, so you can't work around the horrible UI by creating a better programmatic interface for yourself.

Have integrated Xero with Ari. It works like a charm.

We use Xero to control our income, expanses, VAT predictions. Great tool. It takes a while find out how to control all over Xero but in the end it is huge time server and we know pretty sure how the business stands.