This information is not available for applications. In fact, it's a limited information that can be found only on the websites that keep track of the total downloads or installations. However, since there isn't a direct way, the only possibility is to contact the developer of the application and ask him about this details. It's not certain that you will receive this information, but you can try. You can access the Contact US page on the GMAC website to get in touch with a representative that can give you this information.
