Rainbows can be observed whenever there are water drops in the air and sunlight shining from behind the observer at a low altitude angle. It is difficult to photograph the complete semicircle of a rainbow in one frame, as this would require an angle of view of 84°.
The antivirus report shows that this application is completely safe. FootballTech designed the app that lies within the Personalization category. Rainbow Wallpaper HD has been downloaded and installed by over 10K users and the latest update was released on Sep 25, 2020.