We have developed an augmented reality tool for radiotherapy to view the real world scene, i.e. the patient on a treatment couch, combined with computer graphics content, such as planning image data and any defined outlines of organ structures. We have deployed our software to a number of consumer electronics devices (iPad, Android tablets, MS HoloLens). We suggest that, in contrast to other augmented reality tools explored for radiotherapy [1], due to the wide availability and low cost of the hardware platforms considered, associated with their increasing computational and graphic power, our system has strong potential as a tool for visualization of medical information for clinicians and other radiotherapy professionals, as a device for patient positioning for radiotherapy treatment, and as an educational tool for patients to visualize their treatment and demonstrate to patients e.g. the importance of compliance with instructions around bladder filling and rectal suppositories. Accuracy of virtual content placement and user evaluation of our system has been experimentally investigated.