Odoo, formerly known as OpenERP, is an open-source business application suite developed in Python under the AGPL license. It follows the Open Core software business model and serves a global user base of 2 million.

HubSpot is a software platform that consolidates data, teams, and customers. It includes marketing automation, sales tools, customer service, content management, operations, and commerce solutions to promote business growth.

EspoCRM is an Open Source CRM (Customer Relationship Management) software that allows you to see, enter and evaluate all your company relationships regardless of the type. People, companies, projects or opportunities. Written in PHP and JavaScript.

Pipedrive is a sales pipeline management tool, mostly used by small demanding teams. It organizes your leads in a way you'll always have a great overview of sales, and important deals won't get dropped.

Web-based CRM for sales, service, marketing, and call center operations that allows users to manage customer relationships and customer satisfaction.

On-demand CRM (Customer Relationship Management) services for managing organization-wide sales, marketing, customer support, and orders.

Mautic is marketing automation software (email, social, & more). Install on your own website or create a free hosted account. The simple 3-step setup process takes less than 5 minutes and you'll be ready to reclaim control of your marketing.

Teamopipe is a CRM tool that integrates directly with Gmail, allowing users to manage and nurture customer relationships effortlessly through a seamless web extension.

Amazing CRM on top of Gmail.

Insightly is a web-based application that serves as a project management tool and a Customer Relationship Management (CRM) system. It integrates with Google Apps through a Gmail gadget and supports Google Docs.

The intelligent CRM startups and small businesses love to use.

Jetpack CRM has all of the tools you need to grow your business. It’s also modular, so you can customize it to suit your needs.