Apple iPhone won't connect to insecure website
Solution 1:
If the certificate has expired, but HSTS is enabled, it is not possible to bypass the error message ‘Safari cannot open the page because it could not establish a secure connection to the server’.
To bypass an expired certificate for a site without HSTS, choose Show Details, then ‘visit this website’.
If the certificate is was revoked, a similar error message is shown but it cannot be bypassed.