First, it helps you recruit people. Prospects are automatically added to your CRM when they fill out a form on your website, send you an email or call your number. Second, Bitrix24 comes with free email marketing and other lead management tools. Third, it comes with free Android and iOS apps helping you work wherever you are.
Bitrix24 CRM manual is available here.
If you are interested in buying self hosted editions of Bitrix24, which come with API, CMS and source code, and can be easily customized
and integrated with other tools, please download trial version here.