Abstract: The electronic device (12) comprises means for injecting into a document an annotation application (22) to extend the document. The annotation application (22) is suitable to be executed according to an extended document only in the context of execution of a document return management module (60) of a navigation application (56) on the source data and treated data of the document return management module (60) and by using the same functions as the document return management module (60) and that the document treated by the navigation application (56) comprises graphic elements, the annotation application (22) being suitable for anchoring an annotation (78) to a point of a graphic element of the document independently of the coordinates of the graphic element in the document.