This math app can be used to teach and study the column addition method. The app is easy to use and it has an intuitive interactive interface with customizable colors and other settings. The user can solve random or custom addition problems with small and large numbers. The number of digits in the numbers can be set. The column addition method is also known as columnar addition, long addition or longhand addition. Review by professor Tim Pelton, assistant professor of Mathematics Education at the University of Victoria reviewed the sister app of column addition - column subtraction: “Because no wrong entries are allowed the app provides a passive form of positive reinforcement and your child will likely improve in both confidence and competence with respect to the procedure.” The interface of Column Addition app is similar to Column Subtraction. Endorsed by teachers R. Zeni, Ecole Sandy Hill Elementary, Abbotsford, BC, Canada: "The Math apps by Esa Helttula allow students to practice and reinforce the specific computation strategies taught in class, with as much or as little scaffolding as necessary. They also provide individualized feedback to each student, with an immediacy that is not always possible through pencil and paper practice. Being able to adjust the level of difficulty to suit their needs is also very motivating for the students. I am so glad to have come across this great educational tool!" Easy to Use The numbers are aligned automatically and the user can concentrate on solving the operations for each column. Carrying is handled automatically and it is visualized using a nice animation. After the user solves the operation for each column the correct answer will fly to the right place. The unit of the answer will fly under the column and the ten is carried over the next column. If the user presses the wrong button the answer will appear above the keyboard but it will not move. Features: - The user can add 2 or 3 numbers - The app can provide random problems or the user can input his own numbers - Each number can have from 1 to 5 digits - The current operation for each column can be hidden - The operands of the current operation can be highlighted - The speed of the animations can be set Other iDevBooks math apps iDevBooks math apps have been reviewed and endorsed by Wired.com, IEAR.org, Edudemic.com, Teachers with Apps, and other respected sites and organizations. Feedback and requests for new features New ideas to make this app better are welcome. Please visit idevbooks.com to give feedback. Privacy This app has no ads or in-app purchases and it does not transmit any data during the operation of the app. This app also does not contain any links to other apps or the web.