Project ARA is a modular smartphone concept that allows users to customize their device by adding or swapping out individual modules. It uses an endoskeleton frame and interchangeable modules. Key technologies that enable modularity include UniPro for high-speed communication between modules, M-PHY capacitive connectors that withstand frequent swapping, and electropermanent magnets that securely affix modules without continuous power drain. Potential advantages include lower costs, longer device lifespan through repairs/upgrades, and customization, but disadvantages are increased size/weight and connection reliability issues.