Here is the Doodledroid UI. Everything is on a small toolbar at the bottom of the screen.
Using the main menu, you can import files into Doodledroid.
Here are all the drawing and painting tools in Doodledroid.
When you tap on the button next to the painting tools, it brings up the brush variants and the size and opacity settings.
When you click on the plus sign to add new brushes, these settings come up and you can make lots of adjustments to create new brushes.
You can choose colors on this palette and it also adds recently used colors at the top.
You can also use the HSV sliders to choose your color.