Finally a good alternative to Zoho, Bitrix24 or Quickbooks that I had already used before!
The interface is much nicer and it's easier to find your way around because even if everything is well integrated in this application (Books, CRM and People), these 3 main functions are well separated at the menu level to display only the options we need each time.
The CRM part of Deskera largely replaces my HubSpot that I had before and is less expensive as soon as we want to use email. It's really nice to be able to manage everything from a single application. Also the android application is really fantastic and well thought out.

Here's what's missing to make it even better:
I would also have liked to have a good PM integrated into Deskera so I wouldn't have to use another application for my project management, but fortunately we can use Zapier and Pabbly Connect to automate processes. Also I hope they will add other languages like French for example!