Before Pokemon Go was out in the UK, I made a New Zealand account to play early. But now it is out in the UK, I want to delete Pokemon Go from my New Zealand iTunes account and redownload it to my UK account without losing any of my progress. This is why I need to know if your progress saves to your Google account, or if it saves to your iTunes account. Thanks
In Pokemon Go all your save data is stored on Niantic's servers and is linked to your Google Account (or Pokemon Trainer Account), so deleting the app will not delete your save data and you won't lose any progress. You can easily redownload the app using your UK account. The important part is that you sign in with the same Google Account. If you do that, you will keep all your progress. You will also keep your your data if you download the app on a different phone and sign in with the same Google account.