InvoiceLion is a powerful, efficient and intuitive open-source invoicing tool for small business owners. InvoiceLion has the best features for small business owners of any app out there. We know... because we have tried them all. (MIT)
Cross-platform
jBilling is a web-based enterprise billing and rating system. It manages your subscribers with automatic invoicing (email and PDF) and payment processing (credit cards, checks, direct deposit). Robust, well documented and easy to use! (GPL)
Cross-platform
Siwapp is an open source web application meant to help manage and create invoices in a simple, straightforward way. (MIT)
Cross-platform
3 applications