Apple
Meanwhile how many Apple devices are in the wild, not on the latest iOS? (You can install it but it'll make it dog slow)
Android particularly annoys me. My latest phone is very updated - every month with security updates. I have an Android 2.2 device sitting in a drawer at home. It's usable but there won't be any updates. That obsolescence isn't down to Android IMO but the vendors and their pushing of their next devices.
At some point, you do need to stop supporting older devices.