Location track in react native app in Background and Foreground state

I have an existing react native app. I'm looking for someone to implement the GPS tracking to work for both Android and iOS devices. The tracking I need is for both foreground and background states and even if the app is killed by user. App will ask permission from user for location track. I'm looking for a freelancer who has experience in this particular area. Interested freelancer type LOCATION in your bid request.