iPhone 6 and iPad picking up different location settings for search and ads iPad and iPhone think they're in a different country. All ads and searches default to Hong Kong.

I have checked my location setting on each device and they're set for Australia and I've cleared the history in Safari as suggested elsewhere but no change to the searches and ads. Help required.
Have you checked the DNS setting (in ios) for your wifi access point at home? Don't have access to my phone at the moment but I think it's Settings > WiFi > (your wifi) > advanced (look for the words DNS or URL somewhere)

Sometimes apps suggest putting in a custom url in there, and they essentially work as a proxy. Want to make sure to delete those if there's something in there. I suggest you try connecting at a coffee shop or a friend's wifi to see if the behavior changes. Make sure VPN is off/disabled too. 

On a different tack, it could be how your router is configured, since you're saying the same thing is happening on two separate ios devices. Be good to get in the router and look around, or ask whoever manages the router.