How to retrieve iPhone IDFA from API?

Question

I would like to get the device IDFA. How to get this info from iOS official API ?

Answer 1

IDFA - Identifier for Advertising

isAdvertisingTrackingEnabled -> trackingAuthorizationStatus

From iOS v14 Apple deprecated isAdvertisingTrackingEnabled and moved the logic into AppTrackingTransparency Framework. Now user has to grand a permission to read idfa(in the same way as Location permission)

User can control it via:

#iOS 13
#AdSupport
#ASIdentifierManager.shared().isAdvertisingTrackingEnabled
Settings -> Privacy -> Advertising -> Limit Ad Tracking

#iOS 14
#AppTrackingTransparency
#ATTrackingManager.trackingAuthorizationStatus

#a global flag
Settings -> Privacy -> Tracking -> `Allow Apps to Request to Track` 
#or select an app from list to control every app separately 

#a local flag
Settings ->  -> Allow Tracking 

Implementation

import AppTrackingTransparency
import AdSupport

func getIDFA() -> String? {
    // Check whether advertising tracking is enabled
    if #available(iOS 14, *) {
        if ATTrackingManager.trackingAuthorizationStatus != ATTrackingManager.AuthorizationStatus.authorized  {
            return nil
        }
    } else {
        if ASIdentifierManager.shared().isAdvertisingTrackingEnabled == false {
            return nil
        }
    }

    return ASIdentifierManager.shared().advertisingIdentifier.uuidString
}