Abstract

The mobile versions of services such as Google Maps or Open Street Maps allow the exploration of maps on smartphones and tablets. The gestures used are the pinch to adjust the zoom level and the drag/flick to move the map. In this paper, two new gestures to adjust the zoom level of maps (but also of images and documents) are presented. Both gestures - with slight differences - allow the identification of a target area to zoom, which is enlarged automatically up to cover the whole map container. The proposed gestures are added to the traditional ones (drag, pinch and flick) without any overlap. Therefore, users do not need to change their regular practices. They have just two more options to control the zoom level. One of the most relevant and appreciated advantages has to do with the gesture for smartphones (Tap Tap): this allows users to control the zoom level with just one hand. The traditional pinch gesture, instead, needs two hands. According to the test results on the new gestures in comparison with the traditional pinch, 30 % of time is saved on tablets (Two-Finger-Tap gesture) whereas 14 % on smartphones (Tap Tap gesture).