The iPhone 15's USB

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This time last year, I was unenthusiastic about the release of the iPhone 14 Pro. Despite impressive improvements with its 48MP sensor on its main camera, allowing it to capture the biggest and most detailed photos yet on an iPhone, and stunning 4K video at 24 or 30 fps in Cinematic mode with optical zoom quality, I yawned.

Also: Every product we're expecting at Apple's fall event (and what won't be unveiled)

Why is that? Although you could create much more detailed image files and higher resolution photos with that big sensor, there was no upgrade to the data transfer speed of the USB 2.0 Lightning port.

As any content creation professional has experienced, transferring images and video from your iPhone to your Mac using a Lightning cable is agonizingly slow. First, the Photos app has to synchronize and index the file listings and thumbnails, which takes a while. Then you have to do an import procedure.

If you have a hundred 75MB ProRAW photographs (7500 MB) you need to transfer from your iPhone 14 Pro, it might take you upwards of two minutes at 480 megabits per second or roughly 60 megabytes per second (MB/s), assuming optimal transfer rates.

A five-minute 4K ProRes video clip at 6GB per minute will be roughly 30GB. At that rate, it could take you 8 minutes to transfer that much data over a Lightning cable. If you are using the Photos or iMovie database to store them, the indexing could take significantly longer, as it's not just a simple copy from a mounted file system, and there will be protocol overhead.

Also: Apple's iPhone 15 USB-C may be as slow as Lightning cable

Did I upgrade to the iPhone 14 Pro Max from my iPhone 13 Pro Max last year? Yes, because when you are on the iPhone Upgrade Program, short of loan termination payments, you effectively swap one monthly payment for another. But I have to say that it was not as big of an improvement as I liked because, as a food photographer, it did not improve my creative content workflow or productivity at all; the data transfer was as slow as it ever was.

That was last year. As I write this, the anticipated iPhone 15 launch is just two weeks away. While there are a lot of rumors and spy photos about what components are due to be upgraded (the camera is suspected to incorporate a new "periscope" design for improved optical zoom, among other things), very little is "confirmed" in terms of what we can expect from the phone.

But we know with almost complete certainty that the iPhone 15 will use USB-C. Why is that? Because the European Union has decreed that by the end of 2024, all smartphones and tablets must use the same USB-C connector.

We don't yet have the full specifications on whether any iPhone 15 models have been upgraded to USB 3.2 or USB 4. Regarding Apple's current product portfolio, the latest USB-C iPads have USB 3.2 connectivity, whereas the current iPad Pro models have Thunderbolt 3/USB-4.

USB 3.2 Gen 2 is fast. The theoretical upper limit is 10Gbps, and USB 3.2 Gen 2x2, which no smartphones support today -- only laptops -- is 20Gbps.

Also: Apple may be adding USB-C charging to older iPhones now, too

From a vendor comparison, the Samsung Galaxy S23 Ultra has USB 3.2 Gen 2, a benchmark for current-generation Android devices.

And USB 4/Thunderbolt 3, the same used on iPad Pro and current Macs? 40Gbps or 5,000Mbps per second, an over 80 times increase over USB 2.0 transfer rates.

USB 3.2 Gen 2 on an iPhone will be a welcome change, bringing it to parity with the fastest Android devices. But if we get USB 4 on any iPhone 15 model, that will be quite an upgrade and would leap ahead of Android regarding device connectivity speeds.

Data transfer speed will not be the only advantage of USB-C on the iPhone; it will also allow for increased wattage and, thus, faster charging speeds.

3rd-party Lightning cables are certified under Apple's MFi program for up to 18W, which limits USB PD charge rates. USB PD through a USB-C cable supports up to 240W for desktop computers and other small appliances (such as portable power stations) as a potential replacement for the old-school 110V AC cable.

While I don't expect an iPhone to charge at 240W, we could see it as high as 35W, according to recent rumors. That's even faster than current generation iPad Pros, which charge at 20W.

Also: Can an updated iPad Pro revive a moribund tablet market?

An iPhone with the same charge connector as other devices in its household will allow consumers to standardize on a single cable type. But as we know, and as my ZDNET colleague Adrian Kingsley-Hughes pointed out last year, not all USB-C cables are built the same or support all transfer speeds and wattage limits.

The most recent iPad received a USB-C upgrade, at the expense of this concoction.

We've all got USB-C to USB-C cables strewn around the house for different devices and accessories, and up until now, I've used them fairly interchangeably without thinking about device safety or potential transfer speed. However, I've also bought from trusted suppliers such as Anker, Nomad, and Apple's own USB-C and Thunderbolt cables (for charging my MacBook Pro and my iPad Pro).

Also: Buying a USB-C charger for iPhone 15? Anker's Nano series has all the options

That pack of $15 Amazon Basics USB-C cables introduced in 2020 that I bought for basic charging needs discounted on Prime Day should be okay, as it is 60W rated and supports USB 3.1 Gen 2 (10Gbps). But a random cable that came with some cheap Chinese lighting gadget I have stuffed in my box-o-cables that I occasionally reach for? Probably not.

And just because a cable supports a fast charge rate/wattage doesn't mean it supports USB 3.2. For example, Anker's cables only support faster speeds if you buy their USB-IF certified $35 USB4/Thunderbolt cable with a relatively low bend lifespan, so it won't be your daily driver for charging.

Anker's best-selling $16 Powerline III can handle a 100W load, making it a good charge cable, but you won't be able to move data faster than USB 2.0. So, as a content creator, you'll need a few high-end cables around strictly for data transfer.

This will lead to a certain degree of consumer confusion because most of the cables currently in the sales channel sold by most third parties are not marked as to what wattages and transfer modes they support -- it's already problematic when we think about device connectivity and charge rates in the Android and Wintel laptop ecosystem.

Apple's OEM cables can be trusted with its own equipment, and its USB-C and Thunderbolts are safely interchangeable (although there's a big price difference between the two, and Thunderbolt will be overkill for use strictly as a charging cable.) But as to the rest of the industry?

Also: Why some people are buying MacBook Pros with broken displays

In 2021, the USB Implementer's Forum created new logos for certified solutions under its program. So far, there hasn't been widespread adoption of these logos on 3rd-party cables packaged with many products, only on the more expensive cables sold in retail, such as Anker's USB4 40Gbps mentioned above. And many aren't certified; they simply say "240W" and do not use the official USB-IF logo.

Apple has so far not said if it will adopt these logos for its MFi products or on the iPhone packaging and device, and we also don't know if there will be increased adoption of USB-IF logos by 3rd-parties now that the iPhone will fully support USB-C.

More importantly, we also don't know what happens when a non-MFi USB-C cable (one missing Apple's licensed chip for authentication) is detected by the iPhone 15. Does it refuse to work altogether (something that would more than just irritate the EU), issue a scary warning, or will it charge and transfer data at slower rates?

So which label on a cable becomes more important now, MFi, or USB-IF? Talk Back and Let Me Know.