Vivo has announced two flagship phones that mainly focus on photography, but also come with glass rear panels that can change colour in direct sunlight.

The Vivo V25 and V25 Pro each include rear cases that use colour changing techniques made up of fluorite AG glass covered in tiny crystals. When exposed to UV light, the case can change the hue and revert again after a period away from the sun. This also allows for patterns to be created using stencils, as only the areas hit by UV will change.

Two versions of the V25 will change colour - aquamarine blue and sunrise gold - while one variant of the V25 Pro carries the feature - surfing blue. There will also be diamond black and starlight black models of each respectively, but those do not change colour.

Both handsets come with the same rear triple-camera unit - 64-megapixel main, 8-megapixel super-wide, 2-megapixel super macro - while the V25 Pro has a 32-megapixel selfie camera on the front. The V25 ups that to 50-megapixels. Each of them feature eye autofocus tech.

The V25 Pro ups the ante when it comes to processing though, with the MediaTek Dimensity 1300 running the show. The standard V25 runs on the Dimensity 900.

The V25 Pro also has a 6.56-inch 2376 x 1080 120Hz AMOLED display that curves around the edges. The V25's display is described as 2.5D.

Other features include a 4,830mAh battery (in the V25 Pro).

Both the V25 and V25 Pro are now available in more than 25 markets globally, including Southeast Asia, South Asia, Latin America, and the Middle East, We'll bring you further availability and pricing when we find out more.