Custom Tile App -- 2

Dear Sir/Madam, I need n smartphone app developed that can be used to create custom tile colors. Basically I will start with a blank square tile. The user can pick the base color from a palette. After this they can add to the base color by choosing various colored stone and glass chips. When they are happy with what they see they then can email for a sample of this custom tile. I had began development using Corona SDK but right now I am too busy to commit the time personally to this project. I am thinking that Ideally a percentage slider would be the best way to go for each of the different colored stones that the users adds. Whatever graphics that are required I can supply. I am not sure what is the best way to hand over this project - ideally I'd like someone to develop the basics along with a a user manual for the app in a program such as Corona SDK (or similar that I could purchase and download). I could then take over the development as I will have to add an extensive amount of options and I think it may be more cost effective in the long run. I am open to suggestions. Please get in touch and let me know what you think. Thank You.