Free CRM with a minimum of features and a good android application?

Question

CRM

Need a CRM with the following features. Every feature is required.
1. Mobile application for Android
2. Free for 2 people
3. Communication with the client via e-mail from the mobile client and web-interface
3.1 Wrote a comment on the transaction in CRM clicked the checkbox to the client the letter went from the company's postal address.
3.2 The client replied to the letter, the comment automatically appeared in the deal
3.3 Response templates with the ability to insert data from the deal into the templates (client name, ordered goods, etc.)
4 Visual display of deals in the sales funnel and setting up sales funnels for different types of deals.
5. Good and understandable RESTFul API
5.1 Creating deals via API
5.2 Hook system. The transaction has changed to a specific address, information with the parameters of the transaction is sent (so that you can synchronize the parameters of the transaction in CRM and the order on the site, and also be able to implement the order processing logic depending on what stage the transaction is in CRM)
6. Nice interface. I really like Flowlu, but point 3 is not implemented in it.

Answer 1

of the normal ones, only hubspot and odoo
are no more,
while Flowlu is muddy