The learning of Cameroonian languages is timely. Technologies facilitate somehow this learning, yet they have a force that permits a bringing together of people and the wide dissemination of information. The production of documents in Cameroonian languages and their propagation remain shy to a certain extent because of difficult access to electric power, computer equipment and a reliable internet connection for the many. Learning is listed in the same category as the production and dissemination of documents. Such learning can be done, we suggest, from mobile phones, which numbers are growing dramatically. However, one obstacle is present: phones are not suitable for the simple reason that they do not have certain letters and diacritics in Cameroonian languages. Conviction that such contribution may participate in a burst of development, this paper proposes Cameroon phone keypads for entering data such as SMS in all languages of Cameroon. It exposes three multi-taps and a mono-tap telephone keypad. For instance, the article explains how these keyboards were designed, but also how the characters have been disposed on each keypad.