Your ‘Order: xxxxxxx Complete’ email from RapidSSL includes links to a bunch of intermediate SSL certificates. Will you install the right one? I have seen installing the incorrect intermediate SSL certificate into the certificate chain cause Chrome on Android to declare a site insecure and block users from accessing it, while every other browser accepts it.
This tool helped me fix the issue: https://ssltools.geotrust.com/checker/views/certCheck.jsp. It pointed out that the wrong intermediate certificate was in the chain, and directed me to download a
RapidSSL SHA256 CA - G3 certificate. I chained that with my server’s SSL certificate, and my Android issue went away.