App psychology

I need an App developer who can create, refine, and launch from an initial concept to a finished product ready to go on the App Store. I am a Child Psychologist and I need to create a psychology App for children who experience anxiety, mood problems, and behavioural problems. A mixed storybook/interactive game type format would be attractive. It needs to be sophisticated, child friendly, informative, engaging, and probably colourful! I have the expertise, the concept, the content, and a general idea of how an App look and might be used for each idea, but I need a partner to help me create them. Current App searches reveal very few options for children experiencing mental health and wellbeing distress. It is a niche that has not yet been tapped into, and where Apps have been created, I feel they are clunky and miss the point all together.