Zurmo

SugarCRM   (Compare Project)

License: gpl3

vtiger   (Compare Project)

License: Mozillaish_License

Zenbership   (Compare Project)

Mostly written in JavaScript

License: gpl3

KIT1   (Compare Project)

Mostly written in JavaScript

License: mit

Mautic   (Compare Project)

Mostly written in PHP

License: gpl3

Fat Free CRM   (Compare Project)

Mostly written in Ruby

License: Unknown

ADempiere   (Compare Project)

Mostly written in Java

License: gpl

Compiere ERP + CRM Business Solution   (Compare Project)

License: gpl

OroCRM   (Compare Project)

License: open_software

kitForm   (Compare Project)

Mostly written in PHP

License: mit