While FaceTime can be great in some situations, it's probably not your preferred method of communicating. You can block somebody from FaceTiming you, though it will also block regular calls and messages from them too. To do so, open up FaceTime and tap on the info button next to the contact you want to block, or enter a number in the text bar at the top. Scroll down and tap on "Block this Caller" then "Block Contact" to confirm.
FaceTime can be great for some occasions, like talking to your kids, but it's likely not your first choice for everyday calls. You can disable it so you don't receive any FaceTime calls that you don't want, in case you have a relative that thinks it's the best thing since sliced bread. Simply head to Settings -> FaceTime and toggle FaceTime to off.
iPhone owners are now accustomed to using FaceTime for video calling. With FaceTime installed across Apple's product line, for many the app represents the first and only video conferencing solution they've used. The problem is that with Android devices, callers cannot be reached using FaceTime. Today, Google entered its hat into the ring with Google Duo, a simple one-on-one video calling app.
No, FaceTime audio cannot be used to call land line phones, or any non-Apple devices.
All FaceTime connections must be between two iOS devices. Making or receiving a FaceTime video or audio call requires a compatible iPhone, Pad or iPod touch.
FaceTime calls use data. One advantage is that wireless calling plan minutes are not consumed. On the downside, when using FaceTime over a cellular data connection (not Wi-Fi) the data plan is used.
With most data plans now capped at monthly allotments, keeping track of data usage can be important for wireless subscribers. The amount of data used by a FaceTime video call or FaceTime audio call can be seen in two different ways on an iOS device: