The app also lets you solve for variables using a question mark. This means you could write "6 (6+1) + ? = 50" and MyScript Calculator will replace the question mark with the correct answer automatically.
In my initial testing of this app, I was amazed at how well it understood and converted free handwriting, but once I tried more complex expressions, I was blown away by just how powerful MyScript Calculator really is. The one problem I had with the app, was that you can't resize the display once the numbers have been written and recognized. With the ability to add more math expressions at any time, it seems like there should be a way to resize the area with a pinch-to-zoom type of gesture so there is room to add more variables.
MyScript Calculator is free at the app store and is great for when you want to perform quick calculations and would even be useful for students wanting to find the solutions to more complex problems.