Launching application on call

I am new to iphone ap开发者_Python百科plication. I am creating a new application which should work in background and activate when call comes. I understand truecaller works in similar way.

Thank You

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The multitasking on iPhone isn't like on the others. So you can't run your application really in background excepted you want to use music or something like this.

Also, you can't detect if the user is calling or not.

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An application running in the background has only one way to make itself felt: send a Push Notification