Is this OK to understand that Activity is similar to ViewController in iOS?

Is this OK to understand that Activity is similar to ViewController in iOS?

I am confused to accept a concept of terms in Android as Activity, Servic开发者_Python百科e etc...

Yes, I would say that Activity and ViewController are rather similar. There is just one BIG difference. In iOS you have a delegate to control your application's state, like a new ViewController has started or the application is finished. In Android you do this separately for each activity via onCreate(), onPause(), etc.