I prefer to just have my phone’s fingerprint reader loaded with a non-fingerprint. You can use any part of your body, really. Use your imagination. It’ll be functionally impossible to unlock your phone even using that same part of your anatomy later, even if anyone could guess what it was.

So then your phone will ask for a fingerprint but none of your fingers will ever in a million years actually unlock it. Jack booted thugs are welcome to try; they will fail. To actually use your phone, just enter your PIN or passcode.