iOS 10 is rolling out from today, the latest major upgrade to the Apple-made operating system that powers millions of phones and tablets across the world. We've been using beta versions of the software since June, and here's what we think – and what to expect when the download lands on your device.

There's lots and lots that's new in iOS 10, but at the same time there are no headline-grabbing major features: you're going to notice these changes gradually over time, rather than straight away. In fact, for the first few days of use you might find yourself double-checking to make sure you've actually upgraded.

The lock screen has been revamped, and to us feels more intuitive, with the option to dip into and respond to notifications directly

The visuals of iOS, for example, last revamped for iOS 7 (back in 2013) are largely unchanged again, though notifications have been slightly restyled, and for the better. The Control Center (the shortcut center that pops up when you swipe from the bottom of the screen) has a cleaner, clearer look too, and although there aren't major design changes, it's safe to say iOS is looking better than ever.

The lock screen has been given one of the biggest upgrades this time around, with instant swipe shortcuts (to the camera and the Spotlight screen) and richer notifications that you can open and interact with via a 3D Touch (or a slide and tap, for those on iPads or older iPhones). You can also get into rich notifications as they pop down inside iOS without jumping out of the app you're currently using.

The Control Center is tidier than before but most screens in iOS look very much as they did before

They'll disorientate you at first but the new way of working soon becomes second nature and Apple's obviously put a lot of thought into how users interact with their phone as soon as it's picked up. The new Raise to Wake is another feature that many will find useful, letting you check notifications by lifting up your phone, though it only works on iPhones from this year and last.

We've certainly been powering through notifications more quickly in iOS 10, though of course not all apps have been upgraded to support the new features yet. With these improvements and the tweaked lock screen, dealing with incoming alerts and getting to the information you need works better than ever.

Apps, apps, apps

It's as you dive into and use the iOS 10 apps that the biggest tweaks are noticeable (unlike Google, Apple updates all of its stock apps at the same time as the mobile OS). Apple News and Apple Music both look a lot fresher and – dare we say it – Google-esque, thanks to some bolder layouts and use of more blank space.

One very welcome change is the ability to remove most of the stock apps, including Maps, Contacts, Mail and even Music. However, the likes of Safari, Photos, Messages and Phone remain immovable, and you still can't change the default apps for web browsing, sending email and so on.

That means if you remove the Mail app, iOS won't know what to do when you ask Siri to send an email or tap an email link on the web – obviously Apple really doesn't want you to use Gmail as a replacement. Still, we'd rather have the option to remove some stock apps than not, even if it's a rather half-baked solution for now.

It's inside the stock apps like Music and News where there's most change, and most of them can now be removed if you don't want them

We do like the improvements to Apple Maps, with real-time traffic updates now appearing as you travel, plus the ability to add stop-offs (for gas or food) en route without losing the original directions to your destination.

Those are both features already in Google Maps, incidentally, and it's hard to see Apple continuing to stick with the same policy of updating everything all together once a year for much longer. Surely it makes much more sense to be able to update Apple Maps, Apple Music, Apple Mail and the rest as often as required.

Photos got a big upgrade last year and has been given some clever AI trickery this time around: the Apple app will now recognize search terms like "landmark," "beach," "cats," "sunset" or even specific people, giving you more ways to dig into your library. It actually works very well, identifying everything from "lawns" to "beverages" in our tests, and bringing up results in a flash.

Maps and Photos have been upgraded significantly too, with live traffic updates and diversions in Maps, and smarter searches in Photos

It's also introduced a new Memories feature that uses the metadata linked to pictures (like time and date) to produce short highlight clips and montages set to music. This isn't quite as impressive as the search improvements, but it still made some intelligent suggestions when we tried it (despite most of my iOS photos being screenshots).

Again, it's a direct riposte to what Google has been doing with Google Photos, though Apple is keen to emphasize that all this processing happens on your device and isn't sent to the cloud, so potentially sensitive data stays local.

Together with the introduction of a proper iCloud photo storage service last year, it feels as though Apple is finally getting photos more or less right at last – and with all of our personal photo collections growing with each passing day, this sort of smart, instant searching is going to become increasingly vital.

Messages has been transformed with animations, special effects, stickers and more, though some of the features are only available in iMessage mode

Messages gets perhaps the biggest revamp in iOS 10, and the app is now packed with effects, stickers, GIFs, doodles and "invisible ink" (hidden text that the the recipient has to swipe over to reveal). Like Google with the upcoming Allo, Apple has gone into full-on WhatsApp rivalry mode with its default messaging client, and there's even a mini-app store to plunder for animations and stickers.

Thankfully, if you like your messaging clients simple and clean, all of these extra features are neatly tucked away and you don't really have to wade past them if you never use them. How important this upgrade will be to you depends not just on what you think of WhatsApp and Facebook Messenger but also how many of your contacts are on iMessage, as there's only limited support for these extras in SMS messages.

And really that's the main story of iOS 10. Lots of useful improvements for those of you who rely on the apps that Apple makes, but not so much to talk about (bar some spit and polish for the lock screen) for those of you who rarely touch them. The new features are all welcome and well thought-out, but probably not enough to make you switch if you're already happy with the alternatives on your iPhone.

Siri and behind-the-scenes

Digital assistants like Siri, Google Now and Cortana are where the real innovation is happening on mobile right now, and with iOS 10 Siri has gained the ability to talk to non-Apple apps – according to Apple's demo, you can hail a ride with Lyft, send a message through WeChat or pay using Square Cash, for example.

We weren't able to test this out, as developers are still working on the integrations, but it's a no-brainer of an extra feature. Apple wants you to be able to control your whole mobile experience through Siri and this is definitely another step towards fulfilling the original promise of Siri from nearly five years ago.

In fact, a dig into the developer documentation reveals Siri has just six specific ways to interact with third-party app: make a call, send and receive messages, search photos, start workouts and book rides. Apps like music streaming and email will still be left out as it stands, which is disappointing.

An automatic 'Memories' feature for photos, a smarter Siri and a new Home app are some of the other improvements in iOS 10

We can report that Siri is as chirpy and as fast as ever, very adept at most queries and actions. Apple says a lot of machine learning technology improvements are happening behind the scenes to make the assistant more responsive and more comprehensive than ever, though we haven't seen a massive jump in its capabilities yet.

There are plenty of other tweaks. More 3D Touch actions. More emojis. A new Home app for HomeKit devices. Transcribed voicemails. iOS 10 is both a major and a minor upgrade depending on what your criteria is.

Offering up a traditional "review" of iOS has always been tricky, because everyone on a new or new-ish device gets it anyway, free of charge, and because we all tend to use our phones in different ways. Now that Apple's mobile OS is in its tenth version, and we're usually talking about minor increments, your experience of the latest upgrade is going to be more subjective than ever.

If you use Apple's apps a lot, there's plenty to explore; if not, the lock screen and Control Center are perhaps the biggest tweaks

As we mentioned at the start, iOS 10 ushers in a lengthy list of improved features for its core apps (though we're disappointed that Mail continues to feel rather outdated). Apps like Apple Music and Apple Maps now look and work like more serious competitors to the popular alternatives from Spotify and Google, and that's going to benefit everyone on an Apple device.

At the same time there's very little change in iOS itself, in the nuts and bolts or the look and feel of the software. If you live by Apple's own native apps you're going to have a lot of fun exploring what's new; if not, you'll just shrug and carry on with your life as normal after iOS 10 arrives on your device.

To read about iOS 10 in Apple's own words, check out the Apple website.

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