APNG (animated PNG) images support [Firefox and Safari 8 support it]
APNG is an extension of the Portable Network Graphics (PNG) format, adding support for animated images. It is intended to be a replacement for simple animated images that have traditionally used the GIF format, while adding support for 24-bit images and 8-bit transparency. APNG is backwards-compatible with PNG; any PNG decoder should be able to ignore the APNG-specific chunks and display a single image.
GIF vs. APNG vs. animated WebP: http://littlesvr.ca/apng/gif_apng_webp.html
Support status: http://caniuse.com/#feat=apng (Firefox and Safari 8 support APNG)
Ben Bout commented
WebKit core now supports it too. I guess it's only a matter of time before we'll see it in Google Chrome.
APNG support should normally have already been implemented!
Max Stepin commented
ESA using animated GIF to show Philae landing site before/after:
Is it time for something simple, lossless, not restricted to 256 colors?
Aken B. commented
I think it is an improvement over the GIF workhorse. You just have to put the APNG and GIF to the test and you will see. The results should be crystal clear.
APNG support can be easily introduced with a very little additional code. Please consider it, this is just two week job for one developer.
There are many APNG files already in the Internet, even on Wikipedia!