https://forum.invoiceninja.com/
Invoice Ninja helps freelancers, small businesses, and agencies send invoices, quote work, track expenses, and get paid. Once your account is set up, you can invoice a client in any currency, accept online payments, run reports, and give customers a branded portal to pay and manage their documents — all from the same place.
This guide walks through the parts of the app you’ll actually use day-to-day. Each section explains what something is, when you’d reach for it, and how it connects to the rest of the system.
Invoice Ninja is available on the web and as a native app on iOS, Android, macOS, Windows, and Linux. Everything is synced to the same account, so you can start an invoice on your phone and finish it on your laptop.