I'm making a webapp that is always going to be a webapp. That is, I'm NEVER going to made a native app for any mobile OS. It's always going to be 100% web based.

And like most mobile webapps, it looks and feels a lot better when you add it to the home screen and then run it as a webapp, instead of just running it as a url in the browser.

So I'm wondering if theres any way to assist the user in adding a bookmark to the homescreen? I know how to do it, but I imagine very few normal phone users have ever bookmarked any sites to their homescreen before.

And it doesn't have to be fully automatic. Even just a link on my page bringing up the "Add to Home Screen" prompt would be excellent. Then the user would have to complete the process by actually clicking "Add" (i'm referring to iOS, I don't know the exact process on android but I'm sure it's very similar).

Is there any way to do anything like this?

What I'm NOT looking to do is use a 3rd party service like AddThis. I'm looking for a solution that is entirely local to and part of my own site.