How can i Store my app Details in the Shopify public app

[anitha]

I am working on publishing one public app and need to figure out some storage to store my app details few so that it would be easy for me to know who installed my app already. what about metadata can i store there? and i have so many questions like this: can we create an installation page before installing my app and is that shopify will store those details in metadata or some where so that it would be easy for me to track those. Can any one please answer my questions