Solution 1:

This is possible, and even quite easy!

Well, if we look at how Angular's own promises work, we need to get Bluebird to $evalAsync somewhere in order to get the exact same behavior.

If we do that, the fact both implementations are Promises/A+ compliant means we can interop between $q code and Bluebird code, meaning we can use all of Bluebird's features in Angular code freely.

Bluebird exposes this functionality, with its Promise.setScheduler functionality:

// after this, all promises will cause digests like $q promises.
function trackDigests(app) {
    app.run(["$rootScope",function ($rootScope) {
        Promise.setScheduler(function (cb) {
            $rootScope.$evalAsync(cb);
        });
    }]);
}

Now all we have to do is add a:

trackDigests(app); 

line after the var app = ... line, and everything will work as expected. For bonus points, put Bluebird in a service so you can inject it rather than use it on the global namespace.

Here is a [Fiddle] illustrating this behavior.

Note that besides all the features Bluebird has over $q, one of the more important ones is that Bluebird will not run $exceptionHandler, but instead will automatically track unhandled rejections, so you can throw freely with Bluebird promises and Bluebird will figure them out. Moreover calling Promise.longStackTraces() can help with debugging a lot.

Solution 2:

Library Angular bluebird promises replaces $q service with bluebird. $http also run through bluebird