Users can remix any public app on Glitch, but you might want to encourage your users to remix an app from your own website, blog post or GitHub page.
You can also Import from GitHub.
Remix URL format
Remix URLs have the following format: https://glitch.com/edit/#!/remix/project-name
Populate environment variables on remix
You can also populate the values in a project's .env file on remix. This can be used to automatically set up a project with a user's API keys already in it. Just pop the variable names and corresponding values on the end of your remix URL, like so:
https://glitch.com/edit/#!/remix/project-name?var1=value1&var2=value2...