Importing my sketch into Amadine App and tracing it with DRAW TOOL.

With very easy to set up strokes, after some playing around i found that setting 'smoothness' (at the bottom of the screen) at level 1 is my prefered setting. I like to have very uneven and wobbly strokes. It gives my freestyle illustration that oganic natural feel. 

Using same tool to lock colors on layer underneath, but this time setting it up on 'fill' not stroke. I found Amadine App superior over other vector mobile programs with this coloring method, it works exacly how i want it to work while freestyling. I swap between 'smoothness' lvl1 and 3 settings and don't go higher. After locking main colors I repair all uneven fills using 'selection tool'. Whole process has most natural feel i had on iPad so far.

I create some additional layers to add some lights and shadows as well to freestyle some more details on the go. Most of the time drawing on top layer with stroke and fill simultaniously (like an animal!) ;)  Layer organizing is easy and intuitive.

At the end I imported paper texture to add some more dirt to illustration. Blend modes are quick and easy.

Overall Amadine App became my go to vector app for freestyle illustration. As for my freestyles I'm using only few tools and settings and that's all i need comparing to other apps I've tried it's very light and responsive. It gives me that natural drawing feel using it on mobile device. Real pleasure to work with.