Teamleader is described as 'One central platform to sell, bill and organise your work. Stop the mess with information spread across different tools, Excel sheets, and inboxes, and collaborate efficiently with your colleagues' and is a CRM system in the office & productivity category. There are more than 100 alternatives to Teamleader for a variety of platforms, including Windows, Linux, Online / Web-based, Mac and Android. The best alternative is ERPNext, which is both free and Open Source. Other great apps like Teamleader are Odoo, Harvest, Bitrix24 and Dolibarr.
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.
Odoo (formerly OpenERP) is a suite of open-source business apps written in Python and distributed under the AGPL license, under the Open Core software business model. It is used by 2 million users worldwide to manage companies of all size.
FileMaker is a cross-platform relational database application. It integrates a database engine with a graphical user interface and security features, allowing users to modify the database by dragging new elements into layouts, screens, or forms.
ZenTao is an open source project management tool, supporting Scrum. It integrates product management, project management, bug management and QA management, etc., covering all lifecycle of software development.
Crust CRM is a 100% free and open-source CRM. It's fully featured and includes rich dashboards, automation rules (workflows), collaborative team messaging and much more. You can customise your CRM with the included low-code development platform.