This article focuses on "fundi wa simu," (mobile phone repairers) in rural Kenya and their ideas about mobile phone design. Our study design and analysis were guided by ideas from postcolonial computing; we use our qualitative findings, and outcomes from a drawing exercise, to show existing flaws in mobile phone design, and to explore how repairers' knowledge can lead to handsets that are better suited for rural Kenyans. Our argument is that, by engaging with repairers "[on] their own terms," technologists can expand conversations around designing for the 'developing' world that go beyond building novel smartphone applications. In fact, such conversations can also include reimagining mobile phones, and supporting local repairers' efforts to manufacture them. We conclude by discussing ways to improve upon postcolonial approaches to technology design.