Wearable devices have evolved towards intrinsic human augmentation, unlocking the human skin as an interface for seamless interaction. However, the non-traditional form factor of these on-skin interfaces, as well as the gestural interactions performed on them may raise concerns for public wear. These perceptions will influence whether a new form of technology will eventually be accepted, or rejected by society. Therefore, it is essential for researchers to consider the societal implications of device design. In this paper, we investigate the third person perceptions of a user's interactions with an on-skin touch sensor. Specifically, we examine social perceptions towards the placement of the on-skin interface in different body locations, as well as gestural interactions performed on the device. The study was conducted in the United States and Taiwan to examine cross-cultural attitudes towards device usage. The results of this structured examination offer insight into the design of on-skin interfaces for public use.