It's been said that the best camera is the one that one has with him, the same could also be said of the best writing tool. I've always maintained that one's smartphone is more useful than we are sometimes lead to believe, all that is required is our imagination. It's a shame to see them used as just phones for calls and texts.
E. L. James the author of the popular exotic fiction novel, the 50 Shades of Grey wrote a large portion of her book on Blackberry device while commuting.
Today we walk around with devices in our hands just as powerful as our laptops. And barely scratch the surface of what we could accomplish using these devices.