TransferWise Business Payouts - The international payouts platform for businesses and banks.
Invoice Ninja - Invoice Ninja is a free, open-source solution for invoicing and billing customers.
Harvest - Simple time tracking, fast online invoicing, and powerful reporting software. Simplify employee timesheets and billing. Get started for free.
Flutterwave - 1 API for ACH, card and mobile money payments across Africa
GnuCash - A personal and small-business financial-accounting software, licensed under GNU/GPL and available for Linux, Windows, Mac OS X, BSD, and Solaris.
Billdogg - Beautifully simple invoicing for freelancers