The drawing tool that I used was artpad.art.com. I have to say that I am not the most talented of artists, but this image does somewhat inspire me to want to visit the real thing.
Other online art tools are:
Here’s one that I did using Graffitti Creator
KRSLibrary 
I LOVE what you did here! It inspires me to try these apps.
LikeLike
Thanks Ellie! It really is a lot of fun just to explore and try stuff!
LikeLike