From the FAQ, it seems like this is not as invasive as fingerprints:
"We selected palm recognition for a few important reasons. One reason was that palm recognition is considered more private than some biometric alternatives because you can’t determine a person’s identity by looking at an image of their palm."
"We selected palm recognition for a few important reasons. One reason was that palm recognition is considered more private than some biometric alternatives because you can’t determine a person’s identity by looking at an image of their palm."