Could I lose my Simcity BuildIt city at some point?
Yes, please be very careful to link your city to Facebook. In case you only have one city, you could also link it to Google Play (Android) or Game Center (iOS).
But what you should never do is not to have it linked to anything. In that case, if you lose your mobile, it breaks down, or something similar, you could lose your city forever. In fact it is very common to lose cities for this reason.
The best way to protect your city is to link your city to Facebook. With this, even if your device fails, your city will be saved. And you can recover it from another device without problems. In fact, there are people who have 2 devices linked to the same account to be able to play from any of the devices (for example, a mobile when you are away from home; and a tablet when you are at home).
(*) Contributed by Atlantis