Recently I have been learning about Feather JS. However I am pretty much confused by the difference between Express and Feather. One of the most important reason people use Feather is because of its capability to provide real time API. Can't Express use real time as well? What are the other differences that set Feather apart from Express?
From the docs
Feathers is a tiny, fully compatible wrapper over Express and Socket.io
So it still uses express underneath.
Here am assuming, real time means being able to get data as soon as it's available (this could still be ambigous on how one defines, but yeah rough definition)
So, here real time could just mean pages getting loaded with data in real time (approx) using the underlying socket.io functionality.
So comming back to your question:
Can't Express use real time as well?
You can very well integrate socket.io on your own. Or really any other duplex socket technologies like websocket, or others like long polling, server-sent events etc.
What are the other differences that set Feather apart from Express?
This part is out of scope for SO question. But in simple terms Feather adds more functionality using express underneath.