In Kenya, applications for professional positions are written in English, unless there is a specific request for another language. Always proofread résumés carefully for typographical and grammatical errors. Do not rely solely on spellcheck program.
Many organizations prefer online applications, and may or may not accept hard copies. It can be useful to set up an electronic signature, if possible. There are many tech-savvy individuals in Kenya, and a staff member in a cyber café or other organization that offers IT services will usually be able to assist with establishing a secure virtual signature.