You’ve got your 4K TV, your Apple TV 4K, and your shiny new iPhone X, XR or XS. But how do you watch those sparkly 4K videos from your iPhone on the big screen? Is it even possible?
Most of us are still getting to grips with a 4K world, let alone looking at Samsung’s new 8K TV! We’re able to record 4K videos on our iPhone, stream 4K videos on Netflix, and rent 4K movies from iTunes.
4K video capture is all possible with an iPhone X, XR or XS and an Apple TV 4K. But it still isn’t straightforward to watch those 4K videos from your iPhone on your TV!
- 1 What is 4K?
- 2 Can you AirPlay 4K?
- 3 Can I mirror my iPhone screen in 4K?
- 4 Can I use an HDMI adapter to stream 4K?
- 5 How do you stream 4K video from an iPhone?
- 6 How can I watch 4K video on my Apple TV 4k?
- How to view your iPhone Memories movies on your Apple TV
- How to control Apple TV without the remote
- AirPlay 2 is coming to a TV near you, here’s what it all means
- Apple unveils iPhone 8, iPhone X, Apple Watch Series 3, and Apple TV 4K
What is 4K?
4K is the successor to 1080p HD video. It offers higher definition picture, with a resolution of either 4096×2160 or 3840×2160. Your iPhone records 4K video in the latter resolution, which is sometimes called UHD (Ultra High Definition).
To watch 4K videos in full quality, your screen needs to have enough pixels on it. The Retina iMac does, but surprisingly your iPhone X, XS, or XR doesn’t. Even the iPhone XS Max has only 2688×1242 pixels in its display.
Don’t be mistaken, this more than enough for a screen that size!
But 4K videos capture more detail than you can appreciate on such a small screen, which is why most people watch 4K videos on a large 4K television.
How do I record 4K video on my iPhone?
Most recent iPhones and iPads support shooting video in 4K. Check yours on Apple’s iPhone comparison page, or take a look at your iPhone camera settings below.
- Go to Settings > Camera > Record Video.
- Tap the quality you want to record video at.
- Take note of the storage consumption for each video quality.
Can you AirPlay 4K?
I know what you’re thinking: you’ve got a 4K TV, an Apple TV 4K, and an iPhone X, XR, or XS.
Can’t you just AirPlay your 4K videos from your iPhone to your TV?
Well… Actually, you can’t.
Airplay videos are limited to 1080p HD quality. This is standard HD, but far less resolution than 4K. It’s a limitation with AirPlay itself — so any apps or videos you use it with don’t exceed 1080p HD.
People speculated that AirPlay 2 would raise the video quality, but Apple has made no mention of it. Instead, that service seems focused on bringing existing quality AirPlay to third-party TVs.
When you record a 4K video with your iPhone camera and AirPlay it to your Apple TV, that video is scaled down to 1080p HD.
This does reduce latency between devices, but if you can’t watch your 4K video in full quality on your iPhone or Apple TV — how can you watch it?
What about streaming 4K iTunes videos from my iPhone?
Many of us have iTunes movie libraries that are ever-increasingly being upgraded to 4K. And this is a different matter to when you AirPlay your own home videos.
When you download a 4K video from iTunes to your iPhone, it doesn’t actually download in full 4K quality. This is because your iPhone doesn’t have enough pixels to make that worthwhile.
However, when you AirPlay that iTunes video to your Apple TV, it will stream in 4K.
Rather than receive the video directly from your iPhone, your Apple TV looks it up on iTunes and streams it in the highest quality from there instead.
That’s why your 4K iTunes movies always play in 4K on your Apple TV.
When you sync your iPhone, iPad or iPod with iTunes, those movies automatically save to your iTunes Library!
What about 4K videos in my iCloud Photo Library?
You’d think the principle above would apply to 4K videos from your iCloud Photo Library as well. If AirPlay is limited to 1080p HD, surely the Apple TV can stream your 4K home videos from iCloud.
Yet this doesn’t always seem to be the case.
Some users have reported that their iCloud Photo Library videos are streaming at less than 4K.
Meanwhile, others claim AirPlay offers full video quality, despite its limitation.
Apple states that videos in your Memories folder are available to view in 4K:
Memories automatically creates collections of your best photos and videos, and Apple TV lets you see them in 4K. —Apple
But perhaps that only applies to whatever is selected for Memories, not the other 4K videos in your collection.
Can I mirror my iPhone screen in 4K?
When you use AirPlay to mirror your iPhone screen, your Apple TV matches the pixel resolution of your device.
Since iPhones lack enough pixels to display 4K, this doesn’t result in a 4K stream to your TV.
Can I use an HDMI adapter to stream 4K?
Apple sells a Lightning Digital AV Adapter you can use to connect your iPhone to a TV or projector via HDMI. When you connect your iPhone to a TV or projector with this adapter, it mirrors everything onto the screen.
However, mirroring and video output using this adapter is limited to 1080p HD. This is a limitation of the adapter itself. So even if you’ve got the correct TV and HDMI cable and you’re playing a full 4K video, it still doesn’t work.
It also outputs video content — films, TV programmes, captured video — to your big screen in up to 1080p HD. —Apple
It’s possible this technical limitation will only change if Apple upgrades the iPhone to use USB-C instead of Lightning.
This is the case for iPad Pro, which can stream 4K video using its USB-C port.
How do you stream 4K video from an iPhone?
You can’t use AirPlay since it’s limited to 1080p HD. Mirroring only matches your iPhone screen resolution — which isn’t 4K. And technically, your Apple TV streams 4K videos from iTunes and not from your iPhone.
So how do you stream a 4K video from an iPhone to a TV?
Unfortunately, you can’t.
It’s unclear whether this is an oversight by Apple, a technical limitation, or a ploy to make future products more appealing.
But unless Apple changes the 1080p HD limit of AirPlay, you may as well save your iPhone storage and turn off 4K videos.
How can I watch 4K video on my Apple TV 4k?
Just because you can’t stream 4K video from your iPhone to your Apple TV, doesn’t mean you can’t watch 4K videos on it at all.
In fact, you can stream 4K TV programmes or films over iTunes, Netflix, and other content providers.
Not only that but if your setup is right, you can watch that content in 4K HDR.
What is 4K HDR?
HDR, or High Dynamic Range, is separate to 4K and also available on iPhone X, XR, and XS. It brings a wider range of colors to your display. So you can enjoy blacker blacks and brighter explosions of color.
Your Apple TV 4K plays content at 4K resolution with HDR colors. Together we call it 4K HDR.
What is Dolby Vision?
You may have seen the term Dolby Vision floating around iTunes as well.
Content with Dolby Vision also features enhanced colors using a form of HDR developed by Dolby. To experience it you’ll need an Apple TV 4K and a Dolby Vision compatible 4K television.
Your Apple TV will automatically output HDR or Dolby Atmos depending on which one is compatible with your TV.
How do I set up my TV to watch 4K HDR?
You need to make sure your Apple TV 4K and your 4K TV are correctly set up to get the 4K HDR experience. This includes making sure your TV supports HDR10 or Dolby Vision before you start.
Check with your TV instruction manual which HDMI port to use for HDR content. It may be the second or third port instead of the first. Also, check if you need to enable HDR or Dolby Vision in the TV settings.
Use an HDMI cable compatible with 4K HDR. Not all of them are! Apple recommends using HDMI cables with a Compatible with Dolby Vision badge.
Finally, update the software on your television and Apple TV. Older versions of the software may not be compatible with the current standards of 4K HDR.
Let us know your thoughts in the comments. Do you record video in 4K? If so, where do you watch it in full quality? What is your experience with Apple TV 4K? And what do you think is next for AirPlay?
Dan is a freelance writer based in South West England.
He spent two years supervising repairs as a Genius Admin for Apple Retail and uses that knowledge to keep our troubleshooting guides up to date.
Long before that, Dan turned to Apple products from a musical background. Having owned iPods for years, he bought a MacBook to learn sound recording and production. It was using those skills that he gained a first-class Bachelor of Science in Sound Technology.