The engine.
The engine is in development. This is what it will do.
A tint by itself is only dark glass. The engine is what makes it yours.
It will take two things: your numbers, and the light around you right now. From those it will set the tint, again and again, so the light that reaches you stays near the level you chose.
How the engine will work.
The same engine will run the app. It will make words larger and cleaner, and give you a darker view of bright things through your phone.
Later, the engine could run on glasses made by others. One set of numbers, wherever you look.
Try the idea now.
Set the Light dial at the top of this page. The page keeps your level. That is the engine at its smallest.