We can monitor any application that has a remotely-accessible network interface. At the very minimum, we can do basic port checks to ensure that the application is listening on a given port or ports. More in-depth monitoring is possible, especially if your application has a HTTP-like protocol (using our standard HTTP check functionality).
More advanced checks can also be incorporated into our system by our engineers, and we are currently working on a monitoring extension API that will allow you to design and implement your own checking logic specific to your application. Contact our support team if you are interested in pursuing this.