PhotoMath is a free camera calculator phone app available on Android as well as iOS and Windows. To use point the camera towards a printed mathematical expression and the app gives the solution, step by step solutions are also available. The problem types are limited to those shown in the examples here and it can be a bit tricky to focus the camera sometimes, particularly where problems are very close together on a page but this is rather clever! The app has handwriting recognition.
Experimenting, I have found that the app works if you point the camera at a screen, so one could zoom to an appropriate size first. Try these equations in the Year 7 text on CIMT for example: