How to create a timer in background thread in iOS
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I need to create two timers. One is on the UI thread, the other one is on the background thread. These timers are independent from each other. 

Scenario that I will be using; I basically need this to test the responsiveness of UI thread. TImer in uI thread updates lastUpdatedDatetime property every 200ms in UI thread. There is also a background thread that polls this lastupdatedDatetime property every 200ms.

Does anyone know how can I achieve this?