For some, it’s a daily annoyance. For others, it’s a non-issue. Emails opening slowly on iOS devices, from iPhone to iPad. But what’s going on? And why does it affect some users and not others?
As a software developer, a “coffee-machine conversation” like this can catch your attention. Especially when so many people complain about it. Even more so when it appears to have started as far back as December 2024. So what’s happening here?
It seems to be related to images, and I believe that myself as well. To be fair, nothing is certain. But I have a strong suspicion.
A sluggish problem since iOS 18.1
Since December 2024, around the release of iOS 18.1 or 18.2, this issue seems to have appeared for a large number of iOS users. They open the Mail app and tap on an email. What used to be instantaneous now feels painfully slow. Not minutes, perhaps, but definitely longer than it should take. And it’s noticeable.
Speed is a matter of perception
One often underestimated part of software development is UI/UX. Let’s briefly touch on that before diving into the Mail app issue. We’ve all grown used to the incredible speed of modern computing. And we instantly notice whether something takes 100 or 250 milliseconds. That sounds extreme, but it really isn’t. We pick up on delays like that almost unconsciously.
I’ll skip some of the technical history, like how GUIs and business logic used to compete for processor time. Let’s fast-forward to today: multithreading, asynchronous processing and “always responsive” interfaces. In short, computers used to look frozen when you clicked a button, simply because they were busy.
Today, that’s handled much more gracefully. Multithreading means a computer can do multiple things at once without those tasks interfering with each other. So even when your device is hard at work, you’ll usually see a smoothly spinning indicator or “spinner” on the screen. That tells you something’s happening. It’s working.
The Mail app suddenly feels slow
And now, back to the Mail app. It strongly appears that Apple, in an effort to fight spam, is now sending every image in every email, every time, to Apple’s servers for analysis. The reason? Spammers increasingly hide their messages in images, since most spam filters still rely heavily on text analysis.
Apple is trying to counter this by using AI, part of “Apple Intelligence”, to scan images for suspicious content. A clever idea in theory. But unfortunately, they seem to have forgotten to include a proper “spinner” or loading indicator during that process. As a result, the Mail app feels slow to respond, when in fact it is busy working in the background.
This takes time. The image must be uploaded, analysed and the result sent back to your device. At the moment, this simply feels like a sluggish operation. Apple may have underestimated how noticeable the delay would be and hoped it would go unnoticed. That doesn’t seem to be the case.
Why you might not notice it
Some users don’t experience this at all. If certain settings are disabled, for privacy reasons or otherwise, then the images are not analysed via Apple’s servers. And without analysis, there is no delay. Personally, I didn’t encounter this issue, likely because I’ve disabled “Apple Intelligence”.
Still, many users around the world report the exact same experience. I therefore suspect that Apple is aware of the issue and working on a solution. Officially, they haven’t confirmed anything as far as I know: no acknowledgment of the problem, no timeline and no fix. But this is one of those cases where silence doesn’t mean ignorance. My guess is that they’re quietly working on a solution behind the scenes. That is just Apple’s style.