Yes it seems to work in converted devices, certainly with my Android but maybe the later iPhones lack support. However, the download QR code displayed in your device's "Apps>SmartPhone Link" might be out of date so just get the app directly for your phone type from the relevant store:
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Once you've got the latest version of the SmartPhone app follow the prompts in the App on your phone to set up the BT connection with the nuvi. Officially I don't think Garmin cares much for supporting SmartPhone in older devices anyway, in this latest link the nuvi 3490 isn't listed at all for iPhone:
Code:
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