Guys, I wanted to chime in. When I first got the Mini 4, with IOS 9 build 340 GM, I tried the PiP function. I went to website with an embedded YouTube clip. Played it, unlocked it from website to the normal IOS video player using the new PiP mode.
I then went and loaded Beach Buggy Blitz Racing the older version that has not been updated in awhile in the app store. The game loaded and I swore the audio in game was working while it was the top window or the main app in the list of multitasking or being prioritized. Video was still in a box small, using PiP mode (Safari still had to be loaded in background with the website up inside of it).
While playing the game and hearing all audio from the game to include music and sound effects, video in small PiP box was playing with the audio as well.
The glitch or bug is if somehow with two different apps either using true split screen multitasking mode, or just the slide over thing, THEN you use the PiP mode audio does get messed up and only goes to one instance or app at the top of the list in OS background for priority instead of playing all of them or having a choice to decide which app and audio can be used or heard for one or all apps... I think its a bug/glitch or kink that hopefully Apple will fix.
Now really I do not want to play my game with audio, here a video with audio, then listen to music and a podcast with boring vocals, all at the same time.
Playing a game and hearing a video clip audio with different levels of volume would be awesome; besides it does work at all is cool. Playing two videos at once in split screen multi task mode and or PiP and that would be cool and ok but does not work yet. Listening to a shoutcast music stream with the free radio tuner app and playing my game so i can listen to better music to get more into my game would be cool. (I have not tested that yet). Listening to podcast while gaming or watching video would be cool.
Truly to summarize, Apple and IOS9 is an attempt to catch up to Android, Samsung and what Windows can do.
Here is REAL multitasking..
I loaded up WARFACE (pc game I hate now, fremium) in Windows 7 64 bit using realtek newest audio chip built in sound on intel z97 gigabyte motherboard with 4 real core processor no HT. Using Nvidia 960 gpu with 2 gigs of video ram, system has 8 gigs of ram.
Got into game, even to play coop mode, you have to have a set amount of players in a channel for the map to be loaded or you got to wait all day and cant play. Well I kind of cheated on that front.
While that was all going, alt tab out of the game to Windows 7 desktop.
Loaded VMWARE Player emulating my complete hardware setup minus 2-4 gigs of ram and only using 2 cores instead of four and ran a virtual machine using Windows 8.1 update 3 full screen with emulated hardware enabled gpu graphics ultimately cutting in half all of my physical hardware, so it runs one physical machine and an OS and a virtual machine.
I am of course using SSD's so even with Windows 7 on real hardware and a game going, in my VM machine using WIN 8, it booted being emulated in 15 seconds to desktop. Loaded up Warface complete different install under VM machine, got in the game with a separate account, got into same coop map level channel so we had enough players to play game.
AUDIO was playing whole time with all OS audio as well and from the game on physical machine in windows 7 and VM machine in windows 8. I was able to alt tab from VM full screen in game playing it to my Windows 7 physical system and play that account back and forth.
Playing same game with two accounts, one fake, one real machine, all audio hardware enabled and accessible, video from good gpu enabled via hardware for both machines and accessible at same time, ram, cpu, resources and SSD's.
In essence two computers being multitask-ed together from same single physical hardware at once. Heck If I had more real cores and ram (do have 16gb ram kit sitting here collecting dust) and more powerful GPU or GPU'S in SLI, I could have ran 2-4 Virtual machines in background while I used physical machine in foreground while gpu, cpu, ram and audio and file system are all load balanced and shared with direct access amongst everything.
NOW THAT IS MULTITASKING; you can do this with VMWARE Fusion or ESXI or windows OS implementation. VMWARE Player is for home use and works great, I can play myself at an online video game and both of them were getting high FPS sharing the same mid grade GPU at hardware level at a resolution of 1920x1080p. It does not get more real or fun than that for when your crazy into multitasking. (also shared the same network card with the same latency to game server and speeds)
So Apple has some learning and catching up to do if they want it on a mobile platform because Samsung, Android are already doing it. Of course it eats and drains battery even in standby with screen off but they figured it out.
From my examples with my machine and VM's, all audio was heard and of course could be enabled, disabled, you could choose which one to turn on or off and same goes with multitasking apps in windows os. Not sure if Android gives you that flexibility or Touch Wiz when it comes to multitasking..
Food for thought..
Good luck to Apple, wish they would have completed their futuristic idea instead of giving us some of the functionality which is having bugs and glitches while in use. This is inside of their own OS with their Apps. When developers get on board updating to IOS9 and enabling the same functions, either they will work better or because of issues inside OS itself, crash as well from the same bugs and glitches...
At hardware level, Windows tablets using 64bit weak atom cpu and 2 gigs of ram is still able to do true multitasking, its just slow as heck. It does work though to include audio and volume and everything else. Heck you can even run a VM on one!