Yes, when you want to use a new device you sideload the key file onto it in a secure manner (i.e. USB).
On Android this presents some issues though, since the last I checked the keyfile had to be added to the "SD Card" class storage, which other apps can also access. If you are on android and go this route, be really careful about the types of apps you install that have Storage permissions (good advice in general, of course).
