AI Glasses
The whole category splits on one question: put a display in the lens or not. With a display you accept weight and battery limits; without one you are left with voice and a first-person camera.
Start from what you want the glasses to replace. Navigation, a teleprompter and live captions all need visible information, which means a waveguide display, more weight and shorter battery life. Chipsets have converged, so the ecosystem separates models: whether maps, payments and your smart home are reachable decides if you bought an assistant or a toy.
