Doji

Doji is a technology company focused on making smartphone trade-ins easier for retailers and customers. Its Smart Trade-In platform lets customers exchange used phones for store credit or discounts, helping participating shops offer more flexible payment options and potentially increase sales and average transaction value. Designed primarily for physical stores, the service includes retailer onboarding, installation and staff training, with a fee charged on completed exchanges rather than a fixed implementation cost.

The platform supports device pricing, logistics, reporting and operational management. To assess each phone, it combines a seller questionnaire with electronic testing through Phonecheck and Doji’s AI-based cosmetic inspection system. Devices are photographed from multiple angles, and images are automatically reviewed for cracks and deep marks. Doji works with purchasing partners to provide offers for accepted devices and support the resale of used smartphones.

The company also serves smartphone buyers and businesses that want to sponsor trade-in incentives. Through Usado Store, a Doji business, individuals can sell used phones online or at participating locations in São Paulo.