You can choose from many known artist's styles or create your own. It feels like the variabilities are endless. The paintings can be very detailed with thousands of brush strokes. That also means they can take long to render. A couple of minutes isn't unusual. The magic takes place before your eyes. Zoom in to see the strokes.
Oilist cost about 4 USD and has no in-app purchases.
(Photo by Simon Shu at Unsplash)