A free app for Android, by DelkaToni.

Hair Color Changer is an easy-to-use application that allows you to change the color of your hair. To use it, simply select a photo from your gallery or take a photo with the camera, then use the brush and eraser to paint the area of your hair. You can change the size of the brush and eraser with the size tool at the top left.

After that, you can select the hair dye to be tested using the tool on the top right. You can change the color and brightness as many times as you want.

Once you're done, press the button on the bottom right to save the result or share it.