A free program for Android, by BG.Studio.

Fish On Screen 3D Wallpaper is a live aquarium wallpaper application that will let you experience an amazing 3D effect on your screen. This application will make you feel like you are in an aquarium and the fish are all around you. The background will be a beautiful one and it will give you a feeling of joy and happiness. You can set it as a lock screen or home screen and it will look great on your phone.

You can set it up with many different themes. You can select one of the free themes that are available in the application and set it up as your background. You can change the number of fish or the speed of the fish and the background will be updated accordingly.