How to clear DNS cache on iPhone
After some research and experimentation, I have found that the easiest way to reset the DNS cache on an Apple iOS Device such as an iPhone is to switch WiFi off and on. This works every-time for me.
Why would you want to flush the DNS Cache?
When you enter a website address such as www.bbc.co.uk the operating system accesses a DNS (Domain Name Server) to convert the name into an IP Address. The operating system holds onto a list, know as a cache, of the most frequently and most recently used domain names. This means the system doesn’t need to contact the DNS server every time you want to access a web page. If it did, web browsing would be slower.
If you are moving your website between hosting providers or doing something else which involves changing the IP Address at which the site is hosted and you want to test the change you will need to flush your DNS. For everyone else the remembered or cached IP address will refresh after a few hours or days, depending on the settings on your Name Server.