I don’t open devices more than necessary - on the bus I can’t it literally makes me feel sick to use my phone. I live in an area where it ends up a mix of straight but also windy roads.
On the train to be honest I find myself standing due to seat availability.
So I usually rest when taking public transport. I use it to close my eyes, look out the window or listen to music.
You don't need to open devices to be creative. In fact, you should probably close them and let your mind wander.
In fact these are times when I let my mind be still