I have an app that requires countdown timer. Due date comes from my back-end with rest api. I need to coundown remaining time in my react native app. But I can't use smart phone's time. Because user can be in different timezone / country etc. How i can use server's due date response for react native?

Should I send also remaining time in seconds to user? So I can countdown that remaining time every second? 

```
https://www.example.com/getDueDate [POST] 

```

returns: 

`Y-m-d H:i:s` (future) time like `2021-05-20 23:40:40`

If I use classic countdown approach for javascript, I need to use smart phone's time. But I don't want to use that.

NTP server approach can be tricky for react-native side. It just simple counter.