While keeping the same screen size, Windows Phone 8 operating system and general layout, Nokia has given the Lumia 920 a significant overhaul to address some of its shortfalls, although as we'll find out, some changes aren't as good as others.
Both smartphones have a 4.5in screen with a resolution of 1280 x 768 and pixel density of 331 per inch, and both can be used while wearing gloves. But look more closely, and you'll see that the 925 gets an AMOLED panel compared to the 920's IPS display.
What this means, is more saturation to help colours appear brighter and more vivid; while this lends itself nicely to the bright and bold Windows Phone 8 interface, photographs and the web might start to look overly saturated, as they do with the Samsung Galaxy S3 and S4.
The biggest changes Nokia has made are with the general design of its flagship Lumia. When we reviewed the Lumia 920 we were blown away by its camera, but disappointed in the sheer weight and bulk of the device. At 185g and 70mm wide, the Lumia 920 was a beast of a phone compared to the dainty iPhone 5, weighing 112g and measuring 58mm wide.
To address our complaints Nokia put the 920 on a crash diet to create the 925, stripping away the phone's wireless charging and shaving away at its edges to make the phone lighter and smaller in every direction.
The end result is a phone weighing 139g and now measuring 8.5mm thick compared to the 10.7mm Lumia 920. Personally, we won't miss wireless charging as the charging pad itself still needs to be plugged in, but Nokia will offer a special case to make the 925 work with any charging pads you already own.
Nokia has also made the move from polycarbonate to aluminium for the 925, following in the premium footsteps of the iPhone 5 and HTC One. Now if only Samsung would do the same...
The Lumia 920 has one of the best smartphone cameras we've ever seen, and is undeniably the best at low-light shooting, thanks to its 'floating' lens technology.
Nokia has given the Lumia 925 this same 8.7-megapixel camera, but has upped the ante slightly by adding an extra lens element, taking the total up to six elements, which should help to produce even sharper images than the 920.
As well as a slight hardware upgrade, Nokia has also been busy with the 925's camera application. Called Nokia Smart Camera, the new app has a range of shooting features similar to those found in the Samsung Galaxy S4.
There's a tool for removing unwanted objects from a photo - say a car drives past and ruins the shot, the app will automatically remove the car, replacing it with whatever it blocked. Smart Camera also lets you shoot multiple images at once to pick the best one, and has the option to add artificial motion blur.
Although an exclusive to the 925 for now, Nokia has said Smart Camera will be available as a software update for all other Windows Phone 8 Lumias as part of the company's Amber update later this year.
Processor and storage
Nokia uses the same dual-core 1GHz processor in both the Lumia 920 and 925, and both phones get 1GB of RAM, but unfortunately storage has been cut from 32GB to 16GB and there's still no microSD card slot to increase this. Some networks (Vodafone in the UK) will offer a 32GB version of the Lumia 925 exclusively, but we had hoped the 16GB days for smartphone storage were behind us.
The Lumia 928
Launched in the US as a Verizon exclusive earlier this week, the Lumia 928 is essentially the same phone as the 920 and 925 internally, but it has an OLED display and Xenon flash for the camera. Unfortunately, the 928 will only be sold in the US, so in the UK you only have to choose between the extra storage and wireless charging of the 920, or the aluminium, more pocket-friendly 925.