  This paper presents Finger Based Technique (FBT) prototypes, a novel
interaction system for blind users, which is especially designed and developed
for non-visual touch screen devices and their applications. The FBT prototypes
were developed with virtual keys to be identified based on finger holding
positions. Two different models namely the single digit FBT and double digit
FBT were propounded. FBT technique were applied using two different phone
dialer applications: a single digit virtual key for the single digit FBT model
and a double digit virtual key with audio feedback enabling touch as input
gesture for the later one. An evaluation with 7 blind participants showed that
single digit FBT was significantly faster and more accurate than double digit
FBT. In addition to that, single digit FBT was found to be much faster than
iPhone VoiceOver entry speeds in performing similar tasks. Furthermore, our
research also suggests 11 accessible regions for quick access or navigation in
flat touch screen based smart phones for blind users. These accessible regions
will serve as a usability design framework and facilitate the developers to
place the widget for the blind user for dynamic interaction with the touch
screen devices. As far as is known to the authors, this is a novel suggestion.
