offer SMS backup
something like this: https://discourse.mozilla.org/t/how-to-get-your-sms-messages-from-your-previous-firefox-os-phone-to-your-foxfooding-phone/5225 via app or while upgrading
something like this: https://discourse.mozilla.org/t/how-to-get-your-sms-messages-from-your-previous-firefox-os-phone-to-your-foxfooding-phone/5225 via app or while upgrading