There are a few tools that can track app uninstalls for you. The one I find useful is Uninstall tracking - MoEngage. They give you a complete list of users who uninstalled your app. You can as well deduce what made the user uninstall your app. Best part is you can send Emails to those users ho uninstalled your app through MoEngage dashboard so as to get the feedback or to get those users onboard.
