# A Review on Mixed Reality: Current Trends, Challenges and Prospects
## 6 Application  
By choosing the components of the MR core application and deploying it with a proper architecture and simulation toolkits, an MR application is implemented. The MR application provides preferred services to users. To achieve this, an application first provides connectivity to sensing devices and MR devices such as an HMD installed on the user's face, and enables user interaction by using applications through the UI. User interaction is possible in different ways, such as by voice commands. At this time, an application is performed and, hence, an appropriate analytical algorithm-related scenario is executed. The result of this process is an MR service that renders the result with appropriate visualization techniques. MR applications are practical for decision-making in daily activities. MR provides great benefits for tourist applications by overcoming the limitations of common systems. MR applications provide immersive experiences by merging virtual and real objects. With this, the user can see a virtual representation of a ruined physical object (such as a 3D model) embedded in a real scene in real size. In this visualization, the details of the model and lighting are set according to the user's position [92]. In such immersive experiences, the user can interact with the virtual model in real space, such as opening a door in a historical building. MR applications also handle displaying vivid scenes related to historical objects embedded in a real environment with immersive experiences. For example, a digital diorama visualizes the movement of a historical object, such as an old locomotive, by pointing to them in the mobile device [109], while AR-based applications only augment historical content such as images, videos, etc. with weak interactions. MR-based game applications overcome the limitations of common systems. They provide interaction with game objects embedded in real scenes. For example, in a strategic game, the user moves a game agent on a board using a preferred method, such as voice commands. Then, the system shows the movement of the agent on the board in real space [110], while previous game applications just visualize the game in a digital environment, such as a PC or mobile device, without providing interaction with the game object in the real environment. There are various limitations in common education systems that are overcome by MR concepts. MR-based applications provide an immersive experience for so-called embodied learning. Imaging in an astronomy application, the user moves on a board in a real environment and interacts with virtual objects such as asteroids. Then, the user perceives the external forces affecting the asteroid trajectory using embodied learning [111]. In contrast, in common learning systems, the user utilizes a PC or Mobile to observe astronomy objects without an immersive experience in a real environment. MR opens new capabilities for medical applications with fewer limitations compared to non-MR tools. In MR-based applications all medical data are displayed with the proper size. This information is embedded in the real scene, such as a surgery room. The user, such as a surgeon, can interact with this information using a surgical device. A good example is an MR guidance platform for mitral valve repair surgery. This seamless platform contains the integration of the heart anatomy model, image data, surgery tools, and display devices in the real environment. This application is used as a guidance platform for the surgeon during the mitral repair operation [112]. In contrast, in AR-based medical applications, information is simply overlaid on the patient's body without preserving the actual size for an accurate visualization process. MR provides great benefits in design applications that overcome the limitations of common systems. MR applications create a collaborative environment for design. In such an environment, multiple users can see the virtual object of the design, such as a 3D model. This model is embedded in a real environment with proper size.