Orb-slam has a good comprehensive feeling, that is, pure rotation is easy to lose, and scenes with few feature points are easy to lose. Lsd is slow and has low accuracy, but because it is based on gradual change, it is estimated to be beneficial to indoor and architectural scenes with regular texture. Svo is not suitable for handheld video shooting, and the UAV test data provided by the author is OK. Both orb-slam and lsd have new papers to read this year, and many methods have their own advantages and disadvantages.

For mobile platforms, the current monocular slam algorithm requires high computation and storage, and is not stable enough. There are also stero cameras, rgb-d, other sensor combinations (imu, gps) and so on.