The authors of Touché did a follow-up paper at UIST this year to study this exact question [1]. In brief, you can train a classifier on the impedance profile of

The authors of Touché did a follow-up paper at UIST this year to study this exact question [1]. In brief, you can train a classifier on the impedance profile of specific users, but there are some significant limitations (impedance profiles naturally drift over time, and accuracy doesn't look so good with a lot of users). [1] http://chrisharrison.net/projects/capacitivefingerprinting/CapFingerprinting.pdf http://chrisharrison.net/projects/capacitivefingerprinting/C...