Please try this example. $scope.$watch is called when you leave or enter in page.
<!DOCTYPE html>
<!-- CSP support mode (required for Windows Universal apps): https://docs.angularjs.org/api/ng/directive/ngCsp -->
<html lang="en" ng-app="app" ng-csp>
<head>
<meta charset="utf-8" />
<meta name="apple-mobile-web-app-capable" content="yes" />
<meta name="mobile-web-app-capable" content="yes" />
<!-- JS dependencies (order matters!) -->
<script src="scripts/platformOverrides.js"></script>
<script src="lib/angular/angular.js"></script>
<script src="lib/onsen/js/onsenui.js"></script>
<!-- CSS dependencies -->
<link rel="stylesheet" href="lib/onsen/css/onsenui.css" />
<link rel="stylesheet" href="lib/onsen/css/onsen-css-components-blue-basic-theme.css" />
<!-- CSP support mode (required for Windows Universal apps) -->
<link rel="stylesheet" href="lib/angular/angular-csp.css" />
<!-- --------------- App init --------------- -->
<title>Onsen UI Split View</title>
</head>
<body>
<!-- Cordova reference -->
<script src="cordova.js"></script>
<script src="scripts/index.js"></script>
<!-- -->
<ons-navigator title="Navigator" var="myNavigator">
<ons-page ng-controller="firstctrl">
<ons-toolbar>
<div class="center">Simple Navigation</div>
</ons-toolbar>
<div style="text-align: center">
<br>
<ons-button modifier="light" onclick="myNavigator.pushPage('page1.html', { animation : 'slide' } )">
Push Page
</ons-button>
</div>
</ons-page>
</ons-navigator>
<ons-template id="page1.html">
<ons-page ng-controller="secondctrl">
<ons-toolbar>
<div class="left">
<ons-back-button>Back</ons-back-button>
</div>
<div class="center">Page 2</div>
</ons-toolbar>
<div style="text-align: center">
<br />
<ons-button modifier="light" onclick="myNavigator.popPage()">
Pop Page
</ons-button>
</div>
</ons-page>
</ons-template>
</body>
</html>
<script>
var app = angular.module('app', ['onsen']);
app.controller('firstctrl', function($scope, $http)
{
$scope.$watch(function( $scope )
{
console.log( "Function watched" );
});
});
app.controller('secondctrl', function($scope, $http)
{
});
</script>