Hello Digital-Seed and welcome to the ArtRage forums 
The mobile version of ArtRage, like it's desktop counterpart, comes with some presets for all the brushes/tools, including the Watercolour brush.
The various brush parameters can also be customised by the user while painting via a tools Settings panel.
And if you find yourself with a set of brush parameters you really like, you can save them as a new Preset for future use.
This page has more info about the Tools found in the mobile version of AR and using them: https://www.artrage.com/manuals/artr...ge-ipad/tools/
Maker Of Replica Macoys
Techie Stuff:
ArtRage 6.1.1 ~ 15" Macbook Pro ~ macOS 10.15.7 ~ 4 Core i7 3.1GHz CPU ~ 16GB RAM ~ Wacom Intuos4 M