PDF Reader Pro supports adding shape annotations, such as ovals, rectangles, arrows, lines, etc. You can directly change the color of these shape annotations, including fill color, line color, and so on. Specific steps are as follows:
1. Open a PDF File;
2. Click Tools -> Draw Ovals / Rectangles / Arrows / Lines;
3. Tap Properties at right top and the Properties Panel will expand. There you can customize the shapes' color like Line Color, Fill Color, Opacity and more.