A system for rendering virtual reality content, comprising: a housing to be attached to a head of a user via a strap; optics integrated in the housing, the display optics oriented on an internal side of the housing that is configured for orientation toward eyes of the user when the housing is attached to the head of the user; a holder integrated in the housing, the holder is configured to receive a smartphone , wherein a screen of the smartphone is oriented toward the display optics of the housing, the smartphone having a data connection with the holder to enable data communication between electronics of the housing and electronics of the smartphone; shutter control logic interfaced with the electronics of the housing; optics control logic interfaced with the optics; a processor configured to interface with the shutter control logic and the optics control logic, the processor is configured to set the shutter control logic to successively switch between rendering image data obtained from the screen of the smartphone to only a left eye-side of the optics and then only to a right eye-side of the optics, the processor is further configured to interface with the optics control logic so that rendering is optimized for when the image data is provided to the left and right eye-sides of the optics, wherein the shutter control logic enables display of three-dimensional images from the image data rendered on the screen of the smartphone when viewed through the optics of the housing; and an inertial sensor of the housing, the inertial sensor providing movement and orientation data of the housing, the movement and orientation data of the housing being communicated to the smartphone, wherein the smartphone uses the movement and orientation data of the housing along with movement and orientation produced by an inertial sensor of the smartphone to fine tune movement and orientation of the housing to influence or update a view direction and perspective into a virtual reality scene rendered by the smartphone. a housing to be attached to a head of a user via a strap; optics integrated in the housing, the display optics oriented on an internal side of the housing that is configured for orientation toward eyes of the user when the housing is attached to the head of the user; a holder integrated in the housing, the holder is configured to receive a smartphone , wherein a screen of the smartphone is oriented toward the display optics of the housing, the smartphone having a data connection with the holder to enable data communication between electronics of the housing and electronics of the smartphone; shutter control logic interfaced with the electronics of the housing; optics control logic interfaced with the optics; a processor configured to interface with the shutter control logic and the optics control logic, the processor is configured to set the shutter control logic to successively switch between rendering image data obtained from the screen of the smartphone to only a left eye-side of the optics and then only to a right eye-side of the optics, the processor is further configured to interface with the optics control logic so that rendering is optimized for when the image data is provided to the left and right eye-sides of the optics, wherein the shutter control logic enables display of three-dimensional images from the image data rendered on the screen of the smartphone when viewed through the optics of the housing; and an inertial sensor of the housing, the inertial sensor providing movement and orientation data of the housing, the movement and orientation data of the housing being communicated to the smartphone, wherein the smartphone uses the movement and orientation data of the housing along with movement and orientation produced by an inertial sensor of the smartphone to fine tune movement and orientation of the housing to influence or update a view direction and perspective into a virtual reality scene rendered by the smartphone. <EOS>