Children with fine motor difficulties may accidentally swipe the screen which results in a scroll. You can disable the swipe and provide for buttons to scroll the screen instead. Note that this setting is relevant only for Avaz Picture mode. 

For Avaz 4.0 and above:

Tap Settings >Page Swipe and turn it OFF. This deactivates the page swipe and introduces arrow keys (left and right arrows) for scrolling through the pages. The arrow keys replace the Alarm and Mistake buttons in the picture mode. 

For versions less than Avaz 4.0

Tap Settings > Page up & down keys(under Picture settings) and turn ON to turn off the screen scroll.