For my database/backend, I am using PHP which resides in the folders of a website for a social media iOS app I am developing in Swift. I know the typical backend is Firebase (or something like this) but I want to know if the strategy I am currently using with PHP and a website is a suitable method for managing user data. I am looking for downsides of using PHP, and if it is secure to hold the data on a public web application database rather than in Firebase.