AngularJS 1.5.x $onChanges Not Working with One-Way Binding Changes

Question

I don't understand why $onChanges isn't kicked off when I change a bound primitive in an input. Can someone see what I've done wrong, and explain this in an uncomplicated way? I made a plunkr of a quick test application after I couldn't get it to work in my actual application either.

angular
.module('test', [])
.component('test', {

    template: '<child application="vm.application"></child>',
    controller: 'testCtrl as vm'
})
.controller('testCtrl', function() {

    var vm = this;  

    vm.$onInit = function () {

        vm.application = {
            data: {
                name: 'Test'
            }
        }
    };
})
.component('child', {

    template: '<input type="text" ng-model="vm.application.data.name">',
    bindings: {
        application: '<'
    },
    controller: 'childCtrl as vm'
})
.controller('childCtrl', function() {

    var vm = this;

    vm.$onChanges = function (changes) {
        console.log('CHANGED: ', changes);
    };
})

Answer 1

It's $onChanges and not $onChange.

Also, the onChange only updates when the parent value is changed, not the child. Take a look at this plunkr. Note the console.log only fires when you type in the first input.