Odoo developer mode allows you to make substantial modifications to the Odoo database such as adding fields to your documents and views. You change the default views of your actions and can even create dynamic forms based on other fields within your models.
While Odoo is a powerful application framework the development cycle can be brutal to test changes to your application. By utilizing the developer mode you can test expressions and solve many functional problems without having to restart the server over and over to test simple changes.
Additionally the Odoo developer tool is great for looking at the architecture of forms and views to see how fields are tied to modules, their domains, contexts and other attributes. In this video we explore exactly how we put these tools to use in modifying and creating Odoo applications.
While it can be very tempting to use developer mode to make a great deal of changes to your application there are some drawbacks. Depending on what you modify and change you can lose these changes with future module updates or when you install additional applications into Odoo. This is particularly true for changes to views.
To activate developer mode you just simply write down
for version v7
before # sign you just add it.
for version > v7
You may not see About Odoo menu because there might be odoo debranding module installed.