I have a 640 LTE and I have to install windows 10 for my Ring doorbell

[Windows Central Question]

do I have to get a new phone

 

[shmsnh]

No, you may upgrade your Lumia 640 to Windows 10 Mobile. Go to the Store and download Upgrade Advisor by Microsoft. Follow the instructions. Before upgrading, do remember to make a backup of all your data. It is recommended to do a hard reset after this upgrade.