•A Raspberry Pi and a CMOS camera were successfully employed for analytical purposes.•Conventional DPPH assay can be carried out with consumer electronics.•Results were comparable with data obtained using a research-grade spectrophotometer.•Open-source software libraries and consumer electronics are effetcive tools for chemistry research and education. Microcontrollers and single-board computers are widespread tools for innovative educational labs, for prototyping and for accomplish everyday tasks by expert users. Moreover, these modules are opening new exciting possibilities in the area of biological and chemical assays. In this study a Raspberry Pi computer assembled with 3D printed parts and inexpensive opto-electronic components were employed to analyse the antioxidant capacity of several bottled tea performing diphenylpicryl-hydrazyl (DPPH) tests. A dedicated python software allowed the execution of the analysis controlling the device through a small LCD touch screen or remotely through secure connections with other devices. The Raspberry Pi-based measurements were compared with a research-grade spectrophotometer showing excellent correlation (R2 = 0.9996) and no significant differences (p < 0.05) in the range of measured values. We strongly believe that this approach could support diagnostics progress in resource-poor countries and open new opportunities in research and education.