What's the rule under the displaying UIAlert message "app would like to use your current location"?

In my app I have two tabs. The first tab just controller with some functions. The second tab has MapView with showUserLocation property YES. As I know in general UIAlert message "app would like to use your current location" is displayed when app is launching, but in my raw app this message has time when I d开发者_StackOverflow社区o the firs tap on my second tab.

Would you clarify me how can I manage this issue?

P.S.Sorry, but I didn't find any info about.

Thanks

It's actually better to only request location access when it's necessary. In many apps, some users might not even use the location-based features. Having it only pop up when they hit the second tab is perfectly fine.