I’ve spent two weeks reading iOS 27 beta reports across Apple’s Support Communities, the MacRumors forums and Reddit, and I still can’t tell you whether the battery is better.
That isn’t a hedge, and it isn’t me being careful with somebody else’s product. I can’t reconcile what people are saying. One iPhone 17 Pro owner reports that battery life has roughly doubled since the update, while another, on the same phone, calls the experience “HORRENDOUS”—capitals his—and says he’s now charging twice a day where iOS 26 needed the once. So I went back through both sets of accounts looking for whatever it is that separates them, and I want to walk you through what I found, because I think it explains most of what is going on in this release.
The great battery disagreement
I’ve been running the public beta on a 16 Pro Max for a fortnight, which is one thin data point out of hundreds. The rest comes from people posting in those three places. Let me give you the good side first, because there’s a lot of it and I don’t want to bury it underneath the complaints.
On a 15 Pro Max the update reads as an entirely new phone: smoother animations, noticeably faster app launches, and a device that stays cold in the hand through all of it. Owners of the 17 Pro say much the same thing in almost the same words—far superior to 26.5.2, battery great, no more excess heat coming off the back of the case during a normal day of use. And an iPhone 11 owner is still getting nine to ten hours a day out of it, sometimes as many as twelve, unchanged since November of last year. That last one surprised me more than all of the rest of it put together.
Now for the unhappy reports. Sharp battery health drops, from 85 to 81 within days of updating. Under four hours of screen-on time from somebody who had gone to the trouble of restoring to 26.5 via IPSW specifically so that he could compare the two releases properly on the same hardware, and who says the phone comfortably lasted him an entire day beforehand. Charging twice daily on a phone where a single charge was enough a fortnight ago. Heat while charging, heat while apps update, heat for no apparent reason at all—and on one 17 Pro Max, an owner who says the back of the phone is at times too hot to touch or to use the screen on.
For a while I assumed that one of these two groups had to be exaggerating for effect, in the way that people on forums sometimes do. I don’t think that any more.
As for my own phone—it doesn’t help you. I have one 16 Pro Max, I didn’t record what its battery was doing under iOS 26 before I updated, and I have no way of separating the update from a fortnight of using the phone differently because there was something new on it. Whatever impression I’ve formed isn’t evidence, and two weeks of reading people certain in both directions has made me trust it less.
Ten days of indexing
So what actually separates them? Here’s the pattern I eventually noticed. I can’t put a number on how much of the disagreement it covers, because nobody is reporting whether their index had finished, but it’s the only thing I found that lines up.
iOS 27 builds a local index of the contents of your Messages, your Mail, your Calendar and your Photos library, so that the new Siri can reach into all of it on request, and the whole process runs in the background for as long as it needs after you install the update. Reports put the duration of that at anywhere from 24 hours to a full ten days. While it runs, phones get warm and batteries drain hard, and one unlucky 17 Pro Max owner watched the Lock Screen alone eat 20 to 30 percent of a charge in a few hours, and reckoned the phone wouldn’t have survived half a day away from a charger. After it finishes, though, the accounts change completely. Battery life “has been great since indexing finished,” says one of them. Another put it more plainly: “after my phone finished indexing and background updates it became so freaking smooth.”
So when somebody sat down to write may matter as much as which phone they wrote about. That’s my read, and it’s a read rather than a finding.
The older phones are the useful case here. iOS 27 runs on everything back to the iPhone 11, but Siri AI and the Apple Intelligence features behind it need an iPhone 15 Pro or newer — so those phones never build the index at all. And the older phones are the ones with no complaints. The iPhone 11 owner sees no change in battery whatsoever. The iPhone 12 and 13 reports are all performance and no heat. The old phones aren’t doing the work the new ones are doing.
Engadget’s Mat Smith reports the same thing from his own testing, and notes that Apple advises keeping the phone plugged in to speed the process up—which is worth knowing given how much of the complaining happens during exactly that window, and appears nowhere in the reports I read. You can also exclude specific apps from indexing if there are places you would rather Siri didn’t look.
And indexing isn’t the only candidate. Beta bugs, thermal changes, a different battery-health estimate, or simply using a new phone more than an old one would all produce some of this. I can’t separate them from here. Two awkward cases don’t fit my version either. One person’s index has been running for well over 24 hours on a library of 268MB of Messages and 79MB of Photos, with the phone sitting cold to the touch on a charger and apparently doing nothing whatsoever with any of it—which suggests to me that the whole process is capable of hanging somewhere in the middle without ever reporting the fact. Another watched indexing complete on the morning after installing, only for it to start over later the same day and stick there. Neither fits the explanation, and I haven’t seen anybody account for them. One write-up of the beta says flatly that the indexing bar was never the thing to watch. Is it wrong? I think the old-phone evidence is stronger than that. But the argument exists.
Siri, when it works
The best thing I’ve read about this release is one user’s account of asking Siri what the last thing his uncle had asked him to do was.
What happened is that Siri came back with the exact request, out of a conversation that was buried under a great many later messages. He then asked it to find out whether the road in question was still closed to traffic; it went off and searched, returned the correct answer along with the expected date for the reopening, and when he asked it to pass all of that on to his uncle in a message, it did—concisely, and in his own words informatively. His verdict was that this has changed his experience with the iPhone.
Having read it twice, I believed him—and I wouldn’t have believed him about any previous version of Siri. Another user asked it to call a phone number showing on his screen, rather than going through the business of screenshotting it and copying it out by hand, and it just worked. Screen awareness, by several separate accounts from different people on different phones, works flawlessly.
And then other people get nothing at all out of it. “Siri doesn’t work most of the time,” one flatly says; it either sits unresponsive or fails to process the request outright. Network requests never worked at all for another, while the on-device model was fine throughout—which lines up neatly with the split you would expect between local and cloud handling. His summary: “it listens but never actually responds.”
My read is that the on-device half has shipped and the server half hasn’t, and Apple’s own description of the architecture supports it: the orchestrator works from the on-device Spotlight index while server-side requests go out through Private Cloud Compute. It would explain the pattern, at any rate—the local requests land, the ones needing a round trip to Apple’s servers fail, and the app hands you the same unhelpful error either way. Somebody with better access than mine could confirm or kill that in an afternoon. And there’s a second, duller explanation. Siri AI sits behind a waitlist you join in Settings, and until Apple lets you through you’re still on the old assistant rather than the new one — so an unknown number of the people reporting that Siri does nothing may simply not have been given it yet. The waitlist exists to manage server capacity, which cuts both ways: it supports the reading that the cloud half is the strained half, and it means some of those failure reports probably aren’t failures at all.
My own complaints are narrower and duller than any of that, and they are all about the app rather than the assistant. After a fortnight on the 16 Pro Max I get frequent stutters scrolling a long thread, delays when typing where letters arrive behind my thumbs and autocorrect quietly stops, and—the one I would call a bug rather than a rough edge—a Sources popup that opens to show no sources at all. Sources tells you where an answer came from, which in an assistant that talks with this much confidence is not a decorative feature.
Then there is a category of Siri behaviour that took me a while to work out. Pull down Control Center or the notification shade and Siri appears behind whatever it was you were reaching for. Smith hit the same wall and named the cause: Siri can now be summoned by swiping down from the Dynamic Island, and swiping down from the top already opens Control Center on the right and notifications on the left. Three things sharing one edge is two too many. Open the Passwords app and it turns up again, and you’ve got to dismiss it before you can get at any of your passwords. After answering a question it sometimes refuses to leave at all—spinning away on top of everything, ignoring new requests until you fling it off the screen.
And voice activation has gone backwards too, at least for some people. One user can’t reliably call out to Siri from across a room any more, or from the shower to check the time or set a timer. It worked fine with the old Siri on the same phone. That’s the report I’d worry about, because setting a timer by voice was the one thing Siri was reliably good at.
Death by a thousand taps
Nowhere does this beta feel less finished than the keyboard, and in my reading of the reports it isn’t especially close.
It doesn’t register all of your keypresses, and every so often registers a random one instead. Autocorrect barely works. How does that ship? Type quickly in Messages and the second letter of a word capitalises itself for no reason anybody has been able to work out. One user—self-described as a bad typist already—notes that he’s nowhere near as bad as this is making him out to be.
There’s a specific, reproducible version of it in Messages: tap the iMessage bubble to bring up the keyboard and nothing happens at all, so you tap it again. Apparently the touch isn’t registered if you hit the bubble immediately after the screen has changed over. Somebody else noticed that the magnified key preview no longer connects to the letter underneath it—which is the kind of detail I’d never have noticed unprompted, and now can’t stop seeing every time I type.
CarPlay giveth
You can finally scrub! On a 2023 Honda Accord the playback progress bar in Now Playing now responds to touch, where under iOS 26 it appeared to be view-only and ignored you entirely. Drag forward and back within a song, at last.
On connection reliability, it’s a mess, and not in any one direction that I could find. One driver says he hasn’t lost connection, restarted the infotainment system, or reconnected his phone even once since updating—having previously done exactly that on a daily basis or more. Another says his wired CarPlay disconnects constantly while carrying on charging, and that after the first connection of the day he’s got to reboot the phone before the car will see it again. A third reckons the connection fails about 80 percent of the time on his own car, and describes going through a dance of plugging the cable in and unplugging it a number of times whenever he first gets into the driver’s seat; once it does eventually connect, though, it stays connected for the rest of the journey and mostly works well.
Google Maps freezes inside CarPlay for several people, who have to quit and go back in—which is the sort of thing I’d expect a point release to fix and would not wait for. On a 2025 Toyota Camry, CarPlay generally works while Maps specifically is buggy. Beta 2 did sort out the CarPlay reboots that had one user close to reverting to iOS 26 altogether, which is worth remembering when you read any of the beta 1 complaints.
Bits and bobs
Here’s a small one that would annoy me daily, and does. Crop a screenshot in the preview and the crop doesn’t stick; it saves and then shares the whole uncropped image to whoever you sent it to. One user has given up cropping at that stage and now saves to Photos and crops it there instead, which is what I’ve started doing too.
Elsewhere, the Control Center volume slider doesn’t sync with the phone’s actual volume, the Lock Screen opens late after you touch it, and Spotlight icons disappear on at least one phone. There’s a shadow problem with the depth effect on wallpapers, too, though the person who reported it was careful to note (in capitals) that it happens rarely.
For some people Safari is still a mess, with various sites crashing, sites you can’t stay logged into, and sites that simply freeze on you. Tapping on a bookmarks folder to open it frequently launches every single one of the sites contained inside it instead, so you close all of the erroneously launched tabs and go back and try the whole thing a second time. That second attempt usually behaves itself.
On the better side: Photos syncing to a Mac is dramatically faster, with screenshots turning up on the laptop in under a minute where iOS 26 made you notice it was not syncing and prod it manually. The Home app scrolls one combined timeline across multiple security cameras instead of making you hunt for the same moment on each. The Wi-Fi protocol in use now shows up in the details pane in Settings, and long-pressing the App Store icon on the Home Screen says App Updates where it used to say just Updates.
On the hardware side, Face ID has arguably got slower, or at least it feels that way because of the unlock animation added back in iOS 26. Home Screen icons render noticeably darker than they did—one 15 Pro Max owner confirmed the difference by installing the beta on his own phone and holding it directly alongside a 17 Pro Max running the shipping release. Somebody noticed a faint black outline around the icons and now can’t unsee it; somebody else simply prefers the new look. That one isn’t a glitch, as it turns out—Apple has changed how iOS renders complex backgrounds, adding darker outlines around translucent menus and brighter reflections to separate the layers, which is presumably why the icons read darker too.
One user reckons the understated Liquid Glass redesign has lost some of its refraction and looks duller, with the App Library search bar as his example. Push the slider to More Clear and it remains, he says, cloudy on the clearest possible setting.
Another just likes the icons and leaves it there. I’ve left the slider where Apple put it and stopped thinking about it…
Old phones, new tricks
Setting the assistant aside entirely, the performance work is the least disputed part of iOS 27, and I think it’s easily the most interesting. Apple will say the least about it, presumably because “your old phone is faster now” sells nothing.
And over on an iPhone 12, the performance benefits are “absolutely brilliant,” no qualification offered. An iPhone 13 on the public beta gets a smooth interface and a verdict of pretty good for a beta—with the Settings app crashing occasionally and swiping in Spotlight behaving oddly. On newer hardware the language people reach for is consistent almost to the point of repetition, with the same handful of words coming up in report after report—”buttery,” “snappier,” “next level,” “completely brand new.” One long-time user writes that “iOS 27 is better than every 26 final release by far,” which is a beta being measured against shipping software.
Though not everyone agrees with any of that. One can’t say he finds the performance of beta 2 better than 26.5.1 in the first place, and another reports the Home Screen going very laggy when scrolling horizontally between pages of app icons, with glitchy low-framerate app launches on top of that and occasional full-system slowdowns that need a hard restart to clear.
What I would actually do
On compatibility, since that’s what people ask about. Third-party apps are largely fine across the board. N26 and Openbank both work normally, HomeKit accessories are behaving themselves, and Flightradar24 and assorted work applications run without complaint. Filen is half broken, with its Drive and Chats tabs working while Home, Photos and Notes don’t. And iMessage sync struggles badly if you keep a very large archive of messages.
If you’re already on the beta, my advice is to wait out indexing before you decide anything at all, because a lot of the heat and battery complaints I read came from phones that were still indexing, and none of the ones I read from after indexing finished. Give it the full ten days that the longest of those indexing reports describes.
And if you’re still deciding whether to install it at all? I would—but I’d go in knowing that the keyboard and the assistant are the roughest parts of the whole release, and that you touch both of them constantly. Everything else I’ve read suggests this is an unusually good beta. I’m just not certain I’d want it sitting on the phone I need working tomorrow morning.
