This paper presents a novel algorithm for online structure and motion estimation. The algorithm works for general camera models and minimizes object space error, it does not rely on gradient-based optimization, and it is provably globally convergent. In comparison to previous work, which reports cubic complexity in the number of frames, our major contribution is a significant reduction of complexity. The new algorithm requires constant time per frame and can thus be used in online applications. Experimental results show high reconstruction accuracy with respect to simulated ground truth data. We also present two applications in artificial marker reconstruction and handheld augmented reality.