How do I find my iOS device's RAM? Is there a way to find how much RAM is installed in my iOS device?
There are a number of free apps that will provide more information about your device’s internals. Lirium Device Info is one of the better ones.

From the top-left menu, open This Device → System for details about your device’s RAM. For instance an iPhone 7+ has 3 GB of RAM:



Note: I am not affiliated with this app or its developer.