BillGrid.com - BillGrid is an easy to use online invoicing, billing and expense management system that will save you time with tracking clients projects, expenses, invoices and payments.
Xero - Xero is online accounting for your small business.
ChargeOver - ChargeOver automates recurring billing, subscription billing, & payment acceptance. A SaaS that integrates with Xero, Quickbooks, & has an API. Free trial.
Mercury - Mercury is banking* for startups
MinuteDock - Web-based time tracking software designed to integrate with the Xero accounting package.
Keeper Tax - Never miss a tax write off. Keeper automatically finds write offs among bank statements for self-employed people - Real estate agents, Freelancers, Rideshare Drivers, Consultants, and more...