I'm currently checking the state of the art of javascript date pickers, but then I come across the page "Usage share of web browsers" on wikipedia. I decided for my current web project to NOT add any javascript date picker because the usage share of IE nowadays is meaningless and that is the only browser (desktop or mobile) that is not compatible with HTML input type: date.
Check out my open source project: https://github.com/violet-guru/Kynodontas