After stubbornly resisting for years, Apple has finally joined the big-screen smartphone movement with its two latest models, the iPhone 6 and iPhone 6 Plus, which go on sale Friday. But it hasn’t just expanded the screens. It has radically redesigned the iPhone, making it thinner and more curved, and has beefed up everything from the screen to the performance to the battery life and wireless speed.

I’ve been testing the more mainstream of the two models, the 4.7-inch iPhone 6, for about a week now, and I think it’s a terrific phone. In my view, it’s the best smartphone on the market, when you combine its hardware, all-new operating system, and the Apple ecosystem whose doors it opens. That includes a new service called Apple Pay for buying goods in stores and online electronically via the phone; it’s due next month. Apple Pay will only work with these latest iPhones, and Apple’s forthcoming smartwatch.

But this review is just part of the story. While I’ve been testing the iPhone 6, my three colleagues on Re/code’s reviews team have been testing the rest of Apple’s new iPhone and iPhone-related products. Lauren Goode has the lowdown on Apple’s first phablet, the 5.5-inch iPhone 6 Plus, here. Katie Boehret reviews the new operating system, iOS 8, here. And Bonnie Cha’s take on the iPhone’s all-new onscreen keyboard, and its third-party competitors, is here.

Price

The iPhone 6 will start at $199 with a two-year contract for a 16 gigabyte model. Apple is raising the memory on the two higher-priced models, for the same prices they cost on the 5s. For $299, you get 64GB, up from 32GB, and for $399 you get a whopping 128GB, up from 64GB. Without a contract, the three versions cost $650, $750, and $850, respectively.

Which one to get?

Apple sees the iPhone 6 as the direct successor to the iPhone 5s, and as the more mainstream of the two models — a smartphone with a bigger screen and other improvements. So do I. The iPhone 6 Plus is really a different category, a cross between a smartphone and a small tablet, or “phablet.” If you love your iPhone, but want a significantly larger screen, I’d go with the regular 6. If you want something much, much larger — something different — and you love the iPhone, then the Plus is probably for you.

Design

Recent iPhones have rounded corners, but they have flat edges and a screen that stops sharply at the phone body’s edge. The iPhone 6 is thinner, and has curved edges. The screen’s borders also curve slightly to meet the body, and the areas to the top and bottom of the screen have been reduced. The power switch has been moved from the top to the side, for easier access on the taller phone.

The result is that Apple has managed to grow the screen’s real estate by 38 percent compared to the iPhone 5s display, while making the overall volume of the phone just 13 percent larger, and its footprint just 22 percent larger. In my tests, it still fit very comfortably in my hand, in the pockets of my jeans, and even in a shirt pocket.

Bigger screen

Apple last expanded the iPhone’s screen in 2012, when it gave the iPhone 5 a four-inch display, without making it wider, while actually reducing its weight and thickness. But even then, its screen was smaller than that of its chief competitor, the Samsung Galaxy S, which at the time had a 4.8-inch display.

That iPhone, and its four-inch successor, the 5s, proved very popular. At first, larger, wider phones seemed weird (I even compared holding the first Samsung Note to your face to “talking into a piece of toast.”) But for many people, especially in certain countries, the iPhone’s screen began to seem too small, as competing models appeared with bigger and bigger screens.

So the iPhone 6’s 4.7-inch screen is a catch-up feature.

But it’s very well done. It has the same 326 pixels per inch as the 5s, and a higher resolution that allows it to display 720p high-definition video (Apple now calls it the “Retina HD Display”). In my tests, text, photos and videos appeared clear, sharp and vivid, with great color that avoids the oversaturation I have found in some Samsung models.

And, despite the larger screen, all my apps — by Apple and third parties — just worked. None that I tested looked distorted or blurry. Apple says its App Store now offers 1.3 million apps, a new high.

The iPhone 6 screen is still smaller than the display on the latest Galaxy, which measures 5.1 inches, but the new Apple is narrower, and substantially thinner and lighter, even though it’s made of metal, and not the plastic used by Samsung, which to me feels cheap.

Wireless

Apple says the new iPhones have faster Wi-Fi and faster cellular LTE. In my tests, I found the iPhone 6’s Wi-Fi speeds — both downstream and upstream — were roughly double those of the 5s, and about 25 percent faster than those of the Samsung Galaxy S5. But I saw little difference in LTE speeds, either on Verizon or AT&T. The 6 and 6 Plus also have a new type of very short-range wireless, NFC, to enable Apple Pay. This is another catch-up feature: Some other phones have had NFC for a while.

Battery

Battery life on phones depends heavily on how you use them. In my daily use, the iPhone 5s generally lasted from eight to 10 hours between charges. But during my week of testing, the iPhone 6 did better, going 14 or 15 hours. Most people will still have to charge it nightly, but won’t be hunting for plugs during the day.

Camera

The rear camera on the iPhone 6 remains at eight megapixels, but has a new sensor that improves focus and face detection. In my tests, photos were sharper, and brighter — especially in low light — than on the 5s. The front camera is also better, with a larger aperture and better sensor.

Two modes

Both of the new models come with a feature that allows you to switch the entire display between “Standard” mode and “Zoom” mode. In the former, the bigger screens are used to display more content. In the latter, you get larger text and images.

Keyboard

The keyboard is vastly improved. It now quickly predicts what your next word might be, and makes fewer errors. You can also substitute third-party keyboards. Both of these are catch-up features — Android phones already have them — but they are very welcome. In my tests, typing improved dramatically.

Oops

Late in my testing, I dropped the iPhone 6 Apple had lent me for this review. It fell flat on its screen from about five feet onto a concrete driveway when I got distracted while taking a photo. This was entirely my fault. But the entire screen was full of cracks. The phone continued to work perfectly, but Apple sent me another to complete my tests. The moral, which most iPhone users already know: Use a case.

Problems

I had only two problems with the iPhone 6 during my week of testing. First, its width and smooth back can make it feel a bit slippery in your palm until you get used to it (this was not the cause of my dropping incident, as I was holding it with two hands, but the moral above still applies.)

Second, I had trouble at first getting the iPhone 6 to work reliably with my car’s built-in Bluetooth. Apple gave me a solution, which involved removing old, unused devices from my far-larger-than-normal list of devices connected to iCloud. (The company said this had something to do with proper Bluetooth pairing on my particular car model.) But Bluetooth calling in the car worked fine after that. Apple says most customers aren’t likely to have this issue, but it is promising a bug fix soon.

Bottom line

The iPhone 6 is a great upgrade for current iPhone owners, or for anyone, really. It manages to provide a much larger display in a phone that’s still small enough to handle easily. It’s my recommendation for the best smartphone you can buy.