"People want to do more with their mobile phones, but their desire is frustrated by two classes of limitations. One is related to the device, its hardware and software. The other is related to the context, and comprises perceptual, motor, cognitive and social aspects. This paper will discuss some of the opportunities and challenges that this complex scenario presents to multimodality, which can be a key factor for a better design of mobile interfaces to help people do more on their mobile phones, requiring less time and attention." — L Chittaro 2010