The current push function does not support all the native IOS functionality. Since IOS 9, push messages are not delivered to the application if it is in foreground, unless you pass the content-available:1 key.
reference:
I would like to see an additional optional data field NativeKeys that you can provide native key/values to, such they are added to the delivered data alongside the keys that are specifically listed in Playfab.
ie passing a value {content-available : 1} would result in the following being delivered to the device.
{ aps : { Badge: 1, content-available : 1, Message : "message", Title: "title" }}
passing a value {content-available : 1, sound : "ding.mp3" } would result in
{ aps : { Badge: 1, content-available : 1,sound : "ding.mp3", Message : "message", Title: "title" }}
This would be future proofing the playfab platform against any changes in push functionality across the various platforms.