You might want to consider adding "Add to Readmill" buttons to the post-checkout page: https://readmill.com/developers/send-to-readmill https://readmill.com/dev

You might want to consider adding "Add to Readmill" buttons to the post-checkout page: https://readmill.com/developers/send-to-readmill https://readmill.com/developers/send-to-readmill (and no, I'm not affiliated with them, I just think they've built a great platform)