You mean on Safari? CB Connect is tested on Chrome (same engine as Safari), IE, and FF. If you're meaning for Mobile then it is not tested on nor does it support Mobile. Please clarify where your issue is happening.

CB Connect does not support Mobile devices. It's not tested on them. If your device supports it you can try adding Chrome or FireFox to it and see if either gives better results. Aside from that please clarify exactly what's happening and what redirect is not working (after login? if they navigate back to your site are they logged in?).

iPads are mobile devices. They use a mobile version of Safari. It's not the same browser as a desktop. JS functions behave differently on a Mobile device compared to a desktop. For example window.location and window.open behave differently or flat out don't work on Mobile and both of them are used by CB Connect. I do not have an iPad, tablet, or any other such device which is why they are not supported, because I can't test on them.

When you click the button it opens a popup, which is to the social sites authentication page. The social site then sends the user to access token page to authenticate the token and populate the Joomla session or cookie. Now it closes the popup and tells the jQuery if the process was a success or not. If it was it does a redirect to the internal registration/login page to handle registration and login. If it was not then it just reloads the page. What part of this process is not working for you? Have you tested with debug mode and maximum error reporting enable in Joomla global configuration to see if an error is occurring?