Odoo - An all-integrated business app suite to unleash your growth potential.
EspoCRM - EspoCRM is open source CRM (Customer Relationship Management) software that allows you to see, enter and evaluate all your company relationships regardless of the type.
ERPNext - The ERP Software that helps you take full control of your business. ERPNext is both powerful and easy to use.
CiviCRM - A Constituent relationship management for the Civic Sector
Dolibarr - Dolibarr ERP CRM is an Open Source software package for small, medium or large companies, freelancers or foundations to manage business. It's a PHP project built by modules addition (invoice, proposal, contact, stock, order, hr, agenda. .
Less Annoying CRM - A simple customer relationship manager made just for small businesses. Manage contact info, track leads, and never miss a follow-up.