iOS

In iOS 10.x.x, 11.x.x, or 12.x.x

• in SkyPhone > Turn on [Integrated Calling].
  Note: In iOS 13 or later, you can always answer an incoming call without unlocking the phone.
  Note: According to the OS specifications, you cannot receive a SkyPhone call without unlocking if you restart the device. When you restart the device, unlock the device to make a SkyPhone call.

Android

• In Android 5.0 or later, whether you select Show Banners Only or Show the Calling Screen in the SkyPhone notification setting, you can answer calls without unlocking the phone.