It's the iPhone. When setup for captive portal, meaning you must open a browser to get redirected thru possible T&C page or targeted landing page.
Apple Captive Network Assistant (CNA) is a pre-auth test program trying to see if you have Internet access, and is not letting you use a Browser in order to be re-directed correctly.
See KBA-2368: When should I bypass CNA feature.
Smartphone users prefer to use WiFi on their handhelds because of its speed. When a user connects to guest wireless networks, most of the times they are required to provide either a guest pass or a user id/password.
Here are the typical steps in connecting a guest network:
1. Choose the desired wireless network from a list of wireless networks
2. Open a browser and enter the necessary credentials
Users sometimes ignore the second step above and wonder why their apps and email are not working. To avoid such confusing situations to their users, Apple came up with a feature called Captive Network Assistant. This feature unnecessitates opening a browser and causes the device to automatically prompt the user to provide credentials using a pseudo browser.
As you can see this is a great feature and takes out lot of confusion from user's point of view. But it can create couple of issues mentioned in the Troubleshooting Steps above. Apart from that CNA pop is not a fully functional browser.
If your users are reporting any similar issues, it is better to bypass the CNA and check how the connectivity goes.
This bypass feature can be found under the WLANs configuration page on the ZD. It allows to choose the bypass feature by SSID type - Guest, Captive Portal (Web Authentication), and Hotspot.
If you prefer to use CLI to enable the CNA bypass, use the following commands:
1.To enable the feature:
You have all rights in this mode.
ruckus(config-sys)# bypasscna Enter the WLAN services type (for example, web-auth, guestaccess, wispr).
2.To disable the feature:
ruckus(config-sys)# no bypasscna