I use a twiddler while walking. It took a couple of weeks to learn to type with one hand, but eventually it becomes less of a headache. I don't use it with any device, I just use it to write down my thoughts while I walk the dogs and get some air. When I get back home I just dump what I've written. You can easily use it for other things such as a specific cord to key off starting a voice recording, or other computational tasks.
