Calca application enables you to transfer any picture from your device or camera directly onto paper, functioning essentially as a digital drawing aid similar to a camera lucida or projection system. Operation Guide: First, you will require a mounting solution such as a glass container, box, or specialized holder. Recommended options are available on my website erbolamm.com. The source material can be a photograph, illustration, text, or sketch essentially any digital image format. The control panel at the top provides rotation functionality, allowing you to adjust the orientation in degree increments. To define your drawing area, simply drag across any corner of the image. The cropping feature defaults to vertical orientation because the subsequent scaling process matches the image height, preventing blank spaces that might disorient the user. When satisfied with your selection, tap the save icon at the top. The resulting image will appear at full transparency. An adjustment slider positioned at the bottom allows you to modify opacity levels until achieving optimal visibility for tracing. Once camera access is granted, your device display will show the chosen image overlaid on your physical drawing surface. Important: Your device camera must maintain focus on the actual drawing surface, whether paper, wall, floor, or similar. For accurate performance, ensure no objects obstruct the space between the drawing area and your device. While paper remains a common option, holding your phone vertically against a wall enables creation of larger mural-style artwork. A basic tripod or stand angled to your preference facilitates three-dimensional drawing techniques. Demonstration videos and images are accessible through the help section. You may also search for any outline drawing to color as practice material. I suggest listening to calming music and ensuring adequate lighting for an enjoyable experience. Additional information appears in the help section, including tutorial videos from my YouTube channel Tutograti tricks showcasing completed drawings and techniques. Limitations and Notes: This application does not function magically results require practice, and demonstration videos illustrate expected outcomes. Internet searches yield numerous outline drawings suitable for practice. Advertising can be eliminated through a points-based system at no cost. The app does not actually project images a separate projector device would be required. To prevent autofocus interference, avoid moving your hand beneath the camera lens, with visual instructions available in the help section. No account registration is necessary. Sample images are downloadable from a secure cloud folder, or you may search for preferred content online. The application undergoes continuous development, and feedback is welcome at erbolamm.com. Utilizing a proper support stand remains essential, with recommended options detailed in the TRICKS & TIPS section within the about menu. Your input would be valuable in helping me understand whether improvements are needed. Thank you for trying my application.