recording thoughts

I really enjoyed your behind the scenes video last month where you showed us your morning walking routine. You said that during your walk you always have great thoughts and inspiration. Do you have an app or a way that you record those thoughts during your walk so you don’t forget them? I always come up with great thoughts/ideas during my walks and short of brining a pad of paper/pencil with me I always forget what they are by the time I get home. Any tips?