RGB Tool lets you find out all the colors you need in a very simple and quick way.
It features RGB and HSB color models plus color transparency and it displays HEX value.
You can take a picture with the camera or open an image stored on your device to get color information.
It is also possible to extract image palette data of a picture.
Save your preferred colors, so you can easily pick them later or whenever you need.
When you have found your color, you can also print it in a PDF document or using a printer.
This is an open source project, code can be found at https://github.com/fasteque/rgb-tool