A trip to the zoo with my 2 year old nephew let me take some reference photos of animals I might not see while riding my bike around Montréal, including these guys.
I used Sketchbook Pro on the iPad pro as I was reminded about it recently by reports online that has left Autodesk and is now an independent application run by artists. It has been free, but will now be paid. It will be pretty cheap and it's great they will continue to develop and improve it.
The drawing itself is nothing to brag about. I haven't drawn in a while and I did a photoshoot with some acrobats for future art and felt I needed a "warm-up". This came together in just a few hours.