The values passed and when this method should be called are dictated by desired functionality on that particular use case, work with a Wunderkind teammate to determine this.
Wunderkind.shared.trackCustom(String eventName, [String: String] extraData)Wunderkind.getInstance().trackCustom(String eventName, HashMap<String, String> extraData)Wunderkind().trackCustom(String eventName, HashMap<String, String> extraData)Wunderkind().trackCustom(String eventName, Map<String, String> extraData)