The iPhone 6s and 6s Plus are finally available to purchase from the Apple Store and carriers in the UK, and demand is through the roof; with queues at Apple's London Regent Street store winding down backstreets and even through a park.

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But with excited early adopters rushing home to set up their new iPhones, realisation struck for many Apple Watch users. Upon opening the Apple Watch app, users are welcomed by a notification informing them that they're using an iPhone that has been unpaired from the Apple Watch, and that the Apple Watch has to be completely reset in order to be paired with the iPhone 6s or 6s Plus.

Resetting your Apple Watch means you'll lose all your data: exercise data, app data, preferences, watch face customisations, Glances and even data relating to your stride when exercising. Stride data is important for those that like to exercise without their iPhones, as your Watch needs to learn your stride to accurately provide distance and so on, and it can take some time to do this. See also: How to use the Apple Watch Activity app

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It’s not just new iPhone owners either. This issue will affect any iPhone owner that switches device. But don't worry: there is a way for you to save and transfer all your Apple Watch apps and data to be used with your new iPhone, and it’s a lot simpler than you may realise.

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How to keep Apple Watch data when switching iPhones

Step 1) If your old iPhone is backed up to iTunes, make sure it's encrypted. This is very important. For legal reasons, Apple is only allowed to store personal health-related data (which includes exercise data) in protected backups. That means either an iCloud backup (which is protected by your Apple ID's password), or an encrypted iTunes backup. If you run an unencrypted iTunes backup and then restore your Apple Watch, you'll find that everything has been saved except health & exercise data. 

Step 2) Make sure you’re connected to Wi-Fi. Connect to Wi-Fi on your iPhone, as you have to be connected to the internet for certain parts of this how-to.

Step 3) Complete restore. If you’re restoring a backup from an old iPhone, make sure all your apps have finished downloading. Failure to do this may resort in having to reinstall your Apple Watch apps.

Step 4) Open the Settings app on the Apple Watch. On your Apple Watch, press the Home button to access the main app menu and open the Settings app. Once opened, head to General > Reset and tap “Erase all Content and Settings”. Don’t worry – if you’ve connected to Wi-Fi in the previous step, the Apple Watch should automatically create a backup of your apps and data.

Step 5) Wait. Your Apple Watch should reset, a process that shouldn’t take more than five minutes or so. Once its erased all content and settings, it’ll reset and bring you back to the initial setup.

Step 6) Initiate the setup process. On your iPhone, open the Apple Watch app and tap ‘Start Pairing’ and follow the initial Apple Watch setup process. If you’re unsure of how to do this, check out our Apple Watch setup how to.

Step 7) Restore from Backup. Midway through the Apple Watch setup, you’ll be asked whether you want to set up your Apple Watch as a new Watch, or restore from a backup. Tap “Restore from Backup” and you should see a list of Apple Watch backups displayed – select the most recent backup and tap ‘Next’.

Step 8) Continue with the setup process. Follow the initial setup process until its finished. Once finished, you’re fully set up and ready to go! You can take a look at the Activity app to verify your exercise data has transferred, and accessing the app menu on the Apple Watch will confirm whether apps have transferred. If there are apps missing, these can be reinstalled via the Apple Watch app.

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