I've been too lazy to redo the Fingerprint in landscape mode but I will definitely give that a go.
TouchID does not have to be set up in different orientations. If you're having difficulty with it recognizing your fingerprints, redo them (orientation doesn't matter). Here's the process I use for setting up TouchID and it has served me very well across a LOT of devices...
- Wipe out whatever fingerprints are there.
- Add a fingerprint (I start with right thumb, then right index, left thumb, and left index)
- When you're setting up the base part of the fingerprint, you want to let your finger drift a little, but generally keep the central part of your fingerprint in contact with the sensor.
- Tap and release slowly, waiting for the device to tell you to lift your finger off (phones vibrate to indicate this)
- Once the base fingerprint is saved, move on to the edges. Pay attention to what part of the finger you're touching and imagine the initial print in the center having a circle drawn around it on your finger. Using this as a mental guide, work your way around that circle to add the outer portions of that fingerprint.
- Once the fingerprint is done, open that fingerprint up and rename it accordingly (I name mine the way I indicated above). This makes it very simple to modify or remove a specific fingerprint afterward.
Keep in mind that the use of TouchID means that you actually give up a slight bit of privacy in some circumstances. A passcode is something you know, and it can not be compelled through court order. Your fingerprint or your facial image is not protected like this and CAN be compelled through court order.