A head-mounted device configured to align and stabilize images generated by an integrated camera that is physically mounted to the HMD with images generated by a detached camera that is physically unmounted from the HMD, said HMD comprising: one or more processors; and one or more computer-readable hardware storage devices that store instructions that are executable by the one or more processors to cause the HMD to at least: generate a three-dimensional feature map of an environment in which both the HMD and the detached camera are operating in; share the 3D feature map with the detached camera; use the 3D feature map to relocalize a positional framework of the integrated camera based on a first image generated by the integrated camera such that a 6 degree of freedom (6 DOF) pose of the integrated camera is determined; cause the detached camera to use the 3D feature map to relocalize a positional framework of the detached camera based on a second image generated by the detached camera such that a 6 DOF pose of the detached camera is determined; receive (i) the second image of the environment and (ii) the 6 DOF pose of the detached camera from the detached camera; access a depth map of the environment; and generate an overlaid image by reprojecting a perspective of the second image to align with a perspective of the first image and by overlaying at least a portion of the reprojected second image onto the first image, wherein (i) the 6 DOF pose of the integrated camera, (ii) the 6 DOF pose of the detached camera, and (iii) the depth map are used to perform said reprojecting. one or more processors; and one or more computer-readable hardware storage devices that store instructions that are executable by the one or more processors to cause the HMD to at least: generate a three-dimensional feature map of an environment in which both the HMD and the detached camera are operating in; share the 3D feature map with the detached camera; use the 3D feature map to relocalize a positional framework of the integrated camera based on a first image generated by the integrated camera such that a 6 degree of freedom (6 DOF) pose of the integrated camera is determined; cause the detached camera to use the 3D feature map to relocalize a positional framework of the detached camera based on a second image generated by the detached camera such that a 6 DOF pose of the detached camera is determined; receive (i) the second image of the environment and (ii) the 6 DOF pose of the detached camera from the detached camera; access a depth map of the environment; and generate an overlaid image by reprojecting a perspective of the second image to align with a perspective of the first image and by overlaying at least a portion of the reprojected second image onto the first image, wherein (i) the 6 DOF pose of the integrated camera, (ii) the 6 DOF pose of the detached camera, and (iii) the depth map are used to perform said reprojecting. generate a three-dimensional feature map of an environment in which both the HMD and the detached camera are operating in; share the 3D feature map with the detached camera; use the 3D feature map to relocalize a positional framework of the integrated camera based on a first image generated by the integrated camera such that a 6 degree of freedom (6 DOF) pose of the integrated camera is determined; cause the detached camera to use the 3D feature map to relocalize a positional framework of the detached camera based on a second image generated by the detached camera such that a 6 DOF pose of the detached camera is determined; receive (i) the second image of the environment and (ii) the 6 DOF pose of the detached camera from the detached camera; access a depth map of the environment; and generate an overlaid image by reprojecting a perspective of the second image to align with a perspective of the first image and by overlaying at least a portion of the reprojected second image onto the first image, wherein (i) the 6 DOF pose of the integrated camera, (ii) the 6 DOF pose of the detached camera, and (iii) the depth map are used to perform said reprojecting.