Invoice Ninja is a free, open-source solution for invoicing & billing customers. With Invoice Ninja, users can easily create and send professional invoices from any internet-enabled device. Clients can print invoices or download them as pdf files as well as pay online from within the system.
Shopify is a commerce platform that allows anyone to easily sell online, at a retail location, and everywhere in between. It offers a professional online storefront, a payment solution to accept credit cards, and the Shopify POS application to power retail sales.
PieSync for Shopify takes less than 5 minutes to configure and helps you build out your Shopify store by minimizing the number of data errors thanks to its customer sync. New shoppers move directly into the right marketing segments (following GDPR) along with all of their contact data. When the contact data changes, in any system, PieSync keeps all the fields up to date.