I have an Apple id, and I am building an application in which I am using Apple Push Notification Service, but I am a little confused about that.
Is there any charges for doing this process from Apple?
Is there any limit that it can run on specific number of Devices in which my app is installed?
Apple will never charge you for using its Push Notification services. It’s free and you can send notifications to any number of devices you want/have to.