yes its true.. all the time have some A4 sized sketchbook in my backpack and while traveling at bus or metro, i search for some victims to draw or draw somethings by my imagination
drawing skill is like a knife.. you should keep it sharp all the time by practicing..
no matter how you feel comfortable and easy on digital drawing.. without analog-manual drawing skills, your drawing skill is just a snowflake
i spend 2-3 hours at bus or metro per day.. and these are great chance to keep on practice and stay sharp.. ah also with my light glasses and uncommon-weird look, i get lots of attention and friends in travels : )
do something.