Why get an expensive Pi when I have an old phone?

A maker developing a project with a high-resolution camera, GPS, storage and lighting controls is reconsidering a Raspberry Pi build in favor of a used Android phone. Second-hand Redmi 13C 5G and Huawei Mate 30 5G handsets cost about ¥300-500, and already include cameras, GPS, storage, a clock, battery, touchscreen and mobile connectivity. By contrast, a Pi 4 setup with camera, GPS and storage is estimated at about ¥1,483; adding a clock, battery backup, display and cellular modem raises the estimate to ¥2,317, before batteries. The phone’s USB-C port can connect it to a custom circuit board for controlling lights and sensors. The comparison uses illustrative November 2026 prices, and excludes shared project costs such as the controller board and data plan.

The phone is also proving workable beyond its low cost: the Redmi has been rooted, its camera tested, and scheduled sleep and wake behavior configured. The Huawei is harder to modify but can run a kiosk app. A side-by-side camera test is planned, since megapixel counts alone do not establish image quality. The main uncertainty is whether enough matching phones can be sourced with reliable batteries and consistent camera behavior. If that challenge can be solved, refurbished phones could also simplify digital art installations: a configured handset could run a display and use mobile data for remote maintenance, avoiding dependence on venue Wi-Fi or network access. The broader appeal is giving mass-produced devices a second life while reusing components that would otherwise need to be assembled separately.