From the Developer
Writer is a writing application without the fuss and distraction of a traditional word processor. It's perfect for everything from taking notes to writing a novel on your phone or tablet.
Writer's philosophy is Keep It Simple. Writer tries to be as basic as possible, giving you somewhere to turn your thoughts into text, markdown support, and some statistics. Nothing more. Nothing less.
Note: Files are currently stored stored in sdcard://Writer/. Future versions of Writer will allow you to select a custom directory, share documents through email, and synchronize your documents using Dropbox and Box.net