The advent of feature phones in emerging economies makes them an ideal tool to be used for facilitating and complementing education performed in a formal environment (i.e. schools). However, most of the proposed applications do not take into account the wishes of the teachers to customise the applications for student needs, or easiness to re-create and personalise the educational content. In this paper, we extend the state of the art by presenting the evaluation of EducaMovil, a platform aimed at easing the creating of educational games that allow teachers to customise or create entirely new educational content by being agnostic of the underlying implementation of the games. Teachers have successfully been using EducaMovil to create educational content for mobile games that were later on used by the students both informal (i.e. classroom) and informal environments (i.e. outside the classroom).