I recently wanted to create an animated PNG, but macOS does not include any built in tools to combine multiple PNGs into an APNG file. Here’s an option using Python source code.

No executable needed! Just download pyAPNG by eight04 - download from GitHub and unZIP, or git clone https://github.com/eight04/pyAPNG. Pure Python code, with no dependencies!

Just run python3 and manually enter (copy-and-paste) a bit of code to load a number of input PNGs (with a delay for each), and save the output to a new PNG, e.g.:

from apng import APNG
ap = APNG()
ap.append_file('1.png', delay=600)
ap.append_file('2.png', delay=900)
ap.append_file('3.png', delay=600)
ap.append_file('4.png', delay=600)

Good enough!