Serious Paint is a nice natural media painting app. It mimics oil paint really well. Serious Paint has 26 brushes: oil brushes, blending brushes, pencils, shaders, erasers, and texture brushes. It also has lots of tools including layers, masks, symmetry tools, rotation tools, and guides.This app works well with the S Pen on Samsung Galaxy Note tablets and supports pressure sensitivity. I have been able to get file sizes up to 5000 X 5000 pixels, but any higher and the app crashes on my Samsung Galaxy Note Pro 12.2. You can create new brushes by changing brush settings. These settings are the size and opacity, bristle properties, blending settings, the jitter, how the paint is applied, and stroke settings such as taper, fade, etc. The UI has a pop out accordion menu with brushes listed in the top row, file settings in the middle row, and useful functions like undo and redo, layers, view, and effects. You can customize your button sizes and settings, set stylus and finger settings, and color picker settings. The buttons in the corners control your colors and brushes. When you tap on the color button on the lower left, it brings up the color picker and if you drag out from the color button, you can pick your hue. You can also change the settings on the drag out color button to show different colors or change the opacity. A tap on the lower button on the right brings up the brush menu. Dragging out from that button controls the opacity and brush size. Overall this is very nice app for giving a traditional media look and if you need more help, it has a quick start guide. You can download a free version or a paid version. To change the brush settings and create new brushes you have to get the paid version. The developers of this app are called Creative Science. They have also made a cute app called Paint With Cats. That app is mainly just for amusement and not for any complex painting. However, it is so cute that it is a must-have for cat lovers.
Here is the UI of Serious Paint
This is the accordion menu pop out.
Here is the brushes menu.
This is the Color Picker.
This is the Gallery Section and you can also set your canvas size and import images here.
This is the UI for Paint With Cats. There are several colors and sizes of cats. You can set the activity level of the cats where they walk or fidget. Occasionally you will see a cat wearing a hat or alien feelers. It's just a lot of fun!
I created this painting in Serious Paint using the oil brushes, shader brushes, and the web brush.