How can I make angularjs ngChange handler be called only when user finishes typing

Use ng-model-options in Angular > 1.3

 <input type="text"
         ng-model="vm.searchTerm"
         ng-change="vm.search(vm.searchTerm)"
         ng-model-options="{debounce: 750}" />

Without ng-model-options — In markup:

<input ng-change="inputChanged()">

In your backing controller/scope

var inputChangedPromise;
$scope.inputChanged = function(){
    if(inputChangedPromise){
        $timeout.cancel(inputChangedPromise);
    }
    inputChangedPromise = $timeout(taskToDo,1000);
}

Then your taskToDo will only run after 1000ms of no changes.