@Alberto Calvo As a rule of thumb, it's recommended to analyze data on such interactions in your product analytics tool as well as the in-app guide analytics. Like this, you can see the big picture and better understand the impact of the in-app tool.
Besides the usual "how many people start the guide and how many complete it," look into how much the guide has influenced a specific action within your product.
You can do this by comparing the behavior of the users/accounts that interacted with the guide and those that did not.
Run this analysis for each step of the guide. You may find that just a few of the guide's steps help, while the others barely have an impact.
It's interesting to see which steps; if the impactful ones are towards the end of the guide, you may want to rethink the flow.
We hear great things in the market about Userflow and Appcues also - worth giving them a try.
HOpe this helps