Thanks to 9to5Mac's Mark Gurman, substantially all of the details of Apple's (NASDAQ:AAPL) next-generation small iPhone, which Gurman says will be called the iPhone 5se, are now known ahead of the spring 2015 launch of the device.

Let's take a closer look at what Apple apparently has planned for this next-generation 4-inch iPhone.

Design changes
As KGI Securities' Ming-Chi Kuo predicted a while back, Gurman reports that the new 4-inch iPhone will look pretty much like the iPhone 5s but will ditch the diamond-cut chamfered edges for 2.5D (i.e. curved) cover glass like on the iPhone 6/6s series of phones.

The current iPhone 5s models are only offered in space gray and silver colors. The new 5se, however, is expected to come in the same colors that the current flagship iPhone 6s/6s Plus phones come in: silver, space gray, gold, and rose gold.

Processor and memory
Although Kuo had said that the new iPhone would pack the same A9 processor found inside of the 6s/6s Plus phones, it seems that this won't be the case. Gurman reports that the new 4-inch iPhone will pack an A8 processor and a gigabyte of system memory, which is the same processor and memory configuration that the iPhone 6/6 Plus have.

According to Apple's presentation at its September 2014 product launch event, the A8 chip is about 25% faster in CPU tasks than the A7 is and about 50% better in graphics tasks. Apple's Phil Schiller also said that the A8 is significantly more efficient, enabling much better performance when the chip is stressed over a long period of time.

The CPU cores inside of the A8 ran at 1.4 GHz, but I suspect that as Taiwan Semiconductor Manufacturing's (NYSE:TSM) 20-nanometer chip manufacturing technology has gotten more mature, Apple might be able to run the chip at higher speeds. I would not be surprised to see the CPU cores inside of the A8 run at 1.5 GHz to 1.6 GHz for a solid performance boost over the implementation in the iPhone 6/6 Plus.

iPhone 6s-class connectivity?
Although the iPhone 5se apparently has the same computing grunt as an iPhone 6/6 Plus, Gurman reports that on the connectivity side of things, the 5se should actually feature the same LTE, Wi-Fi, and Bluetooth connectivity chips as seen in the iPhone 6s, putting it well ahead of the iPhone 6/6 Plus in this respect.

The new phone, in order to support Apple Pay, will reportedly feature an NFC chip.

iPhone 6-class camera
Gurman reports that the iPhone 5se will feature the same cameras found in the iPhone 6. Although the iPhone 5s and iPhone 6 cameras seem identical on the surface (8 megapixel and 1.2 megapixel rear/front cameras, respectively), the 6 actually brought some significant rear camera improvements relative to the 5s.

Indeed, the iPhone 6 brought an improved image sensor and the image signal processor inside of the A8 was significantly improved from the one in the A7.

A solid update overall
All told, the new iPhone 5se, aside from what sounds like an awful name, should be a good upgrade for users of older-generation small iPhones who would like to stick to a small device.

What's even more encouraging, though, is that as the larger iPhones blaze the technological trail, those technologies will find their way into new revisions of the more compact iPhone.

Although this means that customers will need to buy the larger iPhones in order to get the best smartphone technology that Apple has to offer, the 4-inch models will still see excellent year-over-year improvements, ultimately serving the market for small phones that's still quite sizable but neglected by most vendors of premium smartphones.