Table 1.

List of user’s requirements.

Requirements/Difficulties	Requirements	Methods for gathering requirements
Senses (Sn)	For each action, there must be a voice associated with it. Use clear images of coins from the Rwandan currency system. Number of images of coins should be ≤5. The size of icons/coins must be big enough to enable the precisions of children when dragging them to the right place. Ignore the background sounds.	Group interviews, observation, literature review, and online open discussion.
Cognitive functions (Cg)	Use of a soft sound that can attract children to use the mobile app. Facilitate direct feedback using an image of the product that is liked by children, such as doughnuts, bananas, and candy. Reduce background colors that can distract children. Better to use 1 background image whose existence is known to children. Use a clear image that tells the user to return to the home screen or to close the app.	Group interviews, observation, literature review, and online open discussion.
Motor function (Mp)	The user interface needs to be responsive to devices with high resolutions such as tablets. Allow the user to repeat actions until the dragged object reaches the target. Choose the app to be in a landscape position.	Group interviews, observation, and literature review.