Amazing musical game app--top mobile app developer required!

Advanced, Senior, Mobile App Developer Required An amazing simple, interactive, musical app designed for children where they play sounds by touching the visual elements. The app needs to be developed for the iPhone / iPad / Android Phone and Tablet You MUST be able to complete these core functions with *excellence*: -animate objects smoothly -coordinate sound with moving objects -animate multiple images at one time -fade sounds in and fade sounds out smoothly with no abrupt glitches / sharp sounds Basic knowledge of music and music in app development is a plus! I’d like to start development for the iPad/iPhone and if we work well together, then we'll continue with the Android phone and other tablets for this app. I have more apps that need developed in this same category, so if all goes well, we may continue to work together.