Caution with Online Banking
Do not do any sort of online shopping or banking when connected to an unsecured wireless network. If totally needed, it is safer to use your cellular data than connect to a public network to do your online shopping. The best place to do any sort of mobile online shopping or banking is at home on our own secure wireless network.
If you find yourself needing to do an important financial transaction without using up your cellular data and without a secure network, try setting up a VPN on your phone. It is easy to set up and allows users to securely access a private network and remotely share data over public networks.
For more information about VPNs on iPhones, check out https://help.apple.com/deployment/ios/#/ior9f7b5ff26