Trello - Infinitely flexible. Incredibly easy to use. Great mobile apps. It's free. Trello keeps track of everything, from the big picture to the minute details.

Expensify - Import expenses directly from a credit card to create free expense reports quickly. Approve reports online and reimburse directly to a checking account with one click.

Todoist - Todoist is a to-do list that helps you get organized, at work and in life.

Abacus - Expenses without the 'expense report'

hiTask - HiTask is a free shared task list for your team. The place to plan, organize, and stay in sync.

Zoho Expense - Automate your expense reporting process and streamline the approval flow.