Q: Do you use task manager for iphone??

There isn't much of a need for a task manager because of the way iOS multitasks.

Take a look at this Apple doc -> iOS: Understanding multitasking

yeah multi task is built in, But if you are insisting on learning about your battery % usage and CPU % usage, i use a APP called "System Status" which is pretty decent, and another called "myData manager" for tracking Data usage, Give them a try.

Are you possibly referring to something like a to do list? If so, you can search the App store, there are several there. I'm thinking you are not referring to a Task Manager like in Windows to close applications, right?

can you tell me how to close an application in Mac using task manager in windows?

can you tell me how to close an application in Mac using task manager in windows?

Huh? Your question makes no sense.

Firstly, this is the iPhone forum. And secondly, you can't close a Mac application using the Windows Task Manager. They are two completely different operating systems. Windows software does not run on Mac OS.