Hi & welcome! That looks like a super idea! Even experienced gardeners can have difficulty assessing/quantifying sun exposure if they have busy lives, make changes, trees grow, all things that have probably contributed to the development of your product.
The administrator of this very busy site may not have noticed your question in this very busy forum page of the site. If you use the site's "tree mail" feature to send a note to Dave (username Dave,) your question should get his attention.
I think you could do a lot of business with an indoor version also. So many fails with houseplants could be avoided by avoiding the ever-so-common misinterpretation of "low light, medium light, high light" that is so often put on houseplant labels, causing many of the plants to be erroneously put in corners that are much too dark, and darker than what "low light" means in regard to a potted plant inside of a building.
Best luck!