Hi, Diva, I do coloring on my laptop; the online sites I use are thecolor.com and online-coloring.com (they both have simpler pictures to color but can be very relaxing when needing something easy); supercoloring.com (more intricate pictures which is challenging but fun); and Coloring+ which I got from the Microsoft store for free, there is a paid version which lets you save pix and do more, and Coloring+ also has more intricate, challenging stuff. I'll check in to the Color Me app, I see there is a windows version and I think it's free.
I'm so glad you all got me interested in coloring; it is so relaxing!