Billdogg - Beautifully simple invoicing for freelancers
ChargeOver - ChargeOver automates recurring billing, subscription billing, & payment acceptance. A SaaS that integrates with Xero, Quickbooks, & has an API. Free trial.
Free Invoice Generator - A free invoice generator for startups
MinuteDock - Web-based time tracking software designed to integrate with the Xero accounting package.
Bookipi Invoice App - A minimal, beautiful invoice app for freelancers
fusebill - Fusebill is the leading recurring billing and subscription management software for businesses. Try Fusebill for subscription billing made easy!