Short Paper

In this paper we compare one single-screen touch interaction with an automated teller machine (ATM) against two alternative second-screen ATM interactions using a smartphone. In an experimental laboratory study, those three ATM interactions were compared by means of workload (NASA-TLX), usability (SEQ, UMUX) and technology acceptance (selected TAM3-scales and additional scales for trust and security) in a randomized, controlled within-subjects design (n=24). In one smartphone ATM interaction the Personal Identification Number (PIN) was entered on the mobile phone, in the other smartphone ATM interaction the PIN was entered on the PIN-pad of the ATM. The results indicate that overall second-screen ATM interaction - all interaction done on the mobile phone – performed best.