I'm sure a lot of people already suspected this, in 2013 a Facebook engineer proudly stated that they've hacked their way around a dalvik vm limitation[0] for their app to work on Android 2.2-2.3.

It's the attitude that "hacking things to work is okay" is causing extremely bad reliability issues even when using a top of the range android phone or latest iOS device.

Have they ever thought that maybe 18,000 classes is a bit too much?

Absolutely nightmarish way of working.

[0] https://www.facebook.com/notes/facebook-engineering/under-th...