Estonian engineers turn $9 trash phones into pocket-sized data centers

Researchers at the University of Tartu’s Institute of Computer Science in Estonia have repurposed discarded 15-year-old smartphones into low-cost, pocket-sized data centers capable of outperforming popular single-board computers like the Raspberry Pi. By removing batteries from old Google Nexus phones, fitting them with 3-D-printed holders, and powering them externally, the team created clusters costing about €8 (US$9.20) per phone. These clusters run a Linux-based system (PostmarketOS) instead of Android, enabling direct hardware control and enhanced security. The phones, linked as a “master” and “worker” nodes, handle tasks such as AI-powered image recognition and website hosting, demonstrating efficient, high-energy processing in a compact form. The project addresses the environmental issue of e-waste, as billions of smartphones are discarded annually, with most components not properly recycled. By extending the functional life of obsolete devices, the researchers aim to reduce landfill waste and the environmental impact of building new servers.