A friend of mine, Surj Patel, told a while back me he thinks the next big thing in mobile application interfaces will be multi-modal input. That is, we have buttons that allow us to interact with the phone and the fantastic iPhone allows us to use touch. For more of my perspective on touch interfaces, check out a previous post of mine on GigaOm.

Multi-modal interfaces are those that allow us to use multiple mediums to utilize the mobile handset. That is, being able to use touch and voice simulatiously. Google Maps for Mobile just announced anew way of using Google Maps. When conducting a search on the BlackBerry Pearl’s GMM application, you can speak in your search query. Imagine how much time and frustration this will save when trying to interact with Google Maps for Mobile.

Think of how revolutionary this is. Touch interfaces is changing the way we use and look at our mobile handsets, and being able to combine this with voice or other input methods is monumental. As another example, Nokia phones (and some others) feature a hardware accelerometer and some forward-thinking applications are utilizing the accelerometer to do many common functions. For example, if your phone is sitting on a table and it rings, imagine being able to simply turn it over if you want to dismiss the call, rather than having to push a button.

I think Surj is right about multi-modal interfaces.