The NASA Mars Rover API (https://api.nasa.gov/) details 124,550 photos taken by the 'Spirit' rover during her six-year investigation of the martian surface; this app provides access to every image.

Images are grouped together based on the date (the 'martian sol' and its corresponding 'earth date') on which they were taken. Each image is initially displayed with a width that covers 100% of the screen and a height that covers 75% of the screen.

There is the option to alter the image by changing its height/width/blur/brightness/contrast/colour inversion/opacity/sepia value(s); users can also choose to listen to an inspiring soundtrack while viewing the images. Users can, optionally, click on a URL that accompanies each image in order to navigate to the NASA website and see the image in its original dimensions.

An automatic slideshow can be set up with a timing interval in the range of 1-10 seconds, and a 'fullscreen' button enables users to view the images in a sensibly-scaled 'fullscreen' mode.

This app will appeal to anybody with an interest in the exploration of other planets, and particularly to those who are curious about the 'red planet' Mars.