need app to record weight and weight change and target weight

I need an app developed for iOS and Android that will allow me to track my weight and weight change progress. I am looking for a colorful and engaging design style that will keep me motivated to continue using the app. In addition to weight tracking, I would like the app to include goal setting and progress tracking features. Ideally, I would like to be able to set a target weight and track my progress towards that goal. Experience with app development for both iOS and Android is necessary, as well as a strong understanding of user interface design and goal tracking features.