The MAKERphone 2.0 from Croatian kit maker CircuitMess is a build-it-yourself 4G phone that users program themselves. Insert a SIM and it makes real calls and sends real texts, while the software runs on an ESP32-S3 microcontroller. For security-minded tinkerers, the appeal is transparency: the code that controls a cellular device is written by the person using it, not hidden inside a proprietary handset.
Assembly takes about two hours with no soldering — parts click, screw, and plug together. The phone costs $129 on Kickstarter, $40 below planned retail. An expansion port called UMAX accepts six modules, including a camera, speaker, flashlight, environmental sensor, infrared controller, and a blank prototyping board for inventing custom sensors. The phone detects a module when plugged in and adds it to the menu automatically.
CircuitMess also pitches the phone to parents as a first device for children, meaning some programmers will be beginners. The company sells an AI coding tool, VibeBoy, that writes code; each phone includes three months of unlimited AI features. That raises a privacy consideration the source does not address: code generated by an AI model may not be fully understood by the person deploying it, even on a device designed for hands-on control.