When connected to an Android or iOS smartphone, the POP! Cardboard 2.5 from Mr. Cardboard becomes a ticket to the virtual reality 3D world. With various VR (Virtual Reality) and AR (Augmented Reality) apps, a true 3D experience is created. The smartphone's accelerometers serve as sensors to track head movements in compatible apps, providing a genuine feeling of immersion. A cutout at the front allows the use of the smartphone camera, enabling augmented reality apps to project objects into the user's environment.