app.html

<div ng-controller="UserCtrl">
  <p>First user: {{firstUser.get_title()}}</p>

  <p>First group: {{firstGroup.get_title()}}</p>
</div>

<div ng-controller="ListCtrl">
  <p>First list: {{firstList.get_title()}}</p>

  <p>First item: {{firstItem.get_item('Title')}}</p>
</div>

app.js

app.factory('toArray', function () {
  return function (x) {
    var e = x.getEnumerator();
    var r = [];
    while (e.moveNext()) r.push(e.get_current());
    return r;
  };
});

app.factory('ctx', function ($q) {
  var ctx = new SP.ClientContext("/");
  ctx.execThen = (function () {
    var q;
    return function () {
      if (!q) {
        q = $q.when().then(function () {
          return $q(function (resolve, reject) {
            ctx.executeQueryAsync(resolve, reject);
          }).then(function () {
            q = null;
          });
        });
      }
      return q;
    };
  })();
  return ctx;
});

app.controller('UserCtrl', function ($scope, ctx, toArray) {
  var users = ctx.get_web().get_siteUsers();
  ctx.load(users, 'Include(Title)');
  ctx.execThen().then(function () {
    var firstUser = $scope.firstUser = toArray(users)[0];
    var groups = firstUser.get_groups();
    ctx.load(groups, 'Include(Title)');
    ctx.execThen().then(function () {
        $scope.firstGroup = toArray(groups)[0];
      }
    );
  });
});

app.controller('ListCtrl', function ($scope, ctx, toArray) {
  var lists = ctx.get_web().get_lists();
  ctx.load(lists, 'Include(Title)');
  ctx.execThen().then(function () {
    var firstList = $scope.firstList = toArray(lists)[0];
    var items = firstList.getItems(SP.CamlQuery.createAllItemsQuery());
    ctx.load(items, 'Include(Title)');
    ctx.execThen().then(function () {
        $scope.firstItem = toArray(items)[0];
      }
    );
  });
});