This is an application for creating APNGs.
APNGs are an extended PNG format that can be animated in full color and with an alpha channel.
It's not as familiar as GIF, but it's used for LINE stamps (animated stamps) in familiar places.

It is designed to be intuitive and easy to use.
After selecting a photo stored in your device, press the play button, and if everything is OK, save the photo and you are done.
The delay (animation interval) can be freely set for each frame.
For animations with little movement, such as illustration images, you can reduce the file size by optimizing.

Note
If the application does not support APNG, the image will be displayed as a still image.
APNGs cannot be sent with apps that do not support them.
Or it will be sent as a still image.
Images larger than 1000px will be scaled down and imported.
The number of loops will vary depending on the browser or viewing software, but the data is set to the specified number.