Sellsy is described as 'est une solution française de gestion d'entreprise. CRM, facturation, comptabilité et support sont intégrés sur une même interface intuitive' and is an app in the Business & Commerce category. There are more than 50 alternatives to Sellsy for a variety of platforms, including Online / Web-based, Windows, SaaS, iPhone and Android. The best alternative is Zoho. It's not free, so if you're looking for a free alternative, you could try HubSpot or ERPNext. Other great apps like Sellsy are Dolibarr (Free, Open Source), EspoCRM (Freemium, Open Source), Bitrix24 (Freemium) and Zoho CRM (Freemium).
ERPNext is a free and open-source integrated Enterprise Resource Planning (ERP) software developed by Frappé Technologies Pvt. Ltd. and is built on MariaDB database system using a Python based server-side framework.
SuiteCRM provides an enterprise-grade Customer Relationship Management (CRM) application to a global community of users and software developers. It is a robust and credible alternative to Salesforce, Microsoft and the major CRM vendors.