As the number of different Nokia Lumia smartphones increases, is it getting confusing to work out which is the best one to buy.
Are you worried that you are going to be disappointed with anything less than the flagship Lumia 920/925/928 models? I've been using the Lumia 920 as my main phone since early last December, and I've been toting both the 520 and the 720 on a cross-country conference trip in the US. Here's how they shape up.
Both are physically smaller than the Lumia 920 and quite a bit lighter. Having got used to the heft, huge screen and nice spacing of controls around the 920's chassis, I found the smaller phones quite a switch.
Especially with the 520 and its 4-inch screen, I had to remember to keep my fingers away from the viewfinder because the lens isn't set in as far from the edge. But given how many people tell me they find the 920 heavy and bulky, these smaller models should be popular.
The 720 looks and feels like a slimmed down 920, with a 4.3-inch screen; in basic black it's very reminiscent of the earlier Lumia 800. The 520 is a fraction thicker, but has a smaller chassis with different styling. The brightly coloured back (red, blue, yellow or white) curves away from the glass front steeply which makes it feel even smaller — although the edges are still comfortably rounded in your hand.
All the controls are in the same place: volume, power and camera buttons on the right, micro USB at the bottom and headphone socket at the top (and of course the three Windows Phone buttons on the front).
The smooth curves on the 720 make the SIM and micro-SD slot hard to spot (you need the opening tool in the package to get in there). The cover isn't removable, but you can add on a wireless charging cover to charge the 720 on the Lumia 920 charging plate — or any other Qi standard wireless charger.
The 720 has the same solid, responsive buttons as the 920; easy to find with your fingers and you can tell when you've pressed them. The buttons on the 520 feel rather clicky by comparison and not nearly as pleasant to use. You can take the cover off (in fact, you have to, to fit the SIM or micro-SD card). You'll probably want to add a card to up the built in 8GB of storage on both phones; you get 32GB on the Lumia 920, but there's no memory slot if you do run out.
The dual core 1GHz processors in the 520 and 720 would be disappointing in an Android phone; the beauty of Windows Phone is that the extensive GPU hardware acceleration keeps the interface fast and fluid even on lower spec and older chipsets. Browsing the web, playing games, typing documents; it's all about as fast as on any other Windows phone. On the 520, we did find apps took about a second longer to load than on the 920 and some apps were slower to resume when we switched back to them.
Complex processing is marginally slower. It took 22 seconds to capture and process a three-shot HDR image in HDR Photo Cam on the Lumia 920 and 24 seconds on the 720, which means another two seconds until you can take another shot.
DR Photo Cam isn't available for the 520, but the Lazy Lens effects app is; calculating an HD effect in that took three seconds on the Lumia 920 and five seconds on both the 520 and 720.
Battery life is a solid day of moderate-to-frequent use; stream music, use internet sharing or watch non-stop videos and you might need to charge before the evening, but you can do a lot of browsing, emailing, snapping photos, playing games, staying in touch on Facebook and Twitter, and even navigating in Here Maps before you see the battery saver logo.
Both the 520 and 720 have LCD screens that recognise touch gestures when you're wearing gloves which is, if you'll pardon the pun, a nice touch. The screen quality is good too; it has reasonably vibrant and accurate colours and contrast and while the 920 has a clearer screen with richer colours, neither the 520 nor 720 makes you feel like you're looking at a cheap phone screen. The one thing I did notice was how much more visible fingerprints are on the screens of the 520 and 720 than on the 920.
The 720 has a front-facing camera, which the 520 sacrifices to keep the cost down. Opinions are strongly divided on this; some people make video calls all the time, others never use it at all. The 520 has no flash; it doesn't have the 920's fantastic low-light performance, either. The 720 does almost as well as the 920 in low light, getting colours almost as accurate; you'll certainly get a night shot you can use on the 720 and 920. On the 520, probably not.
For photography in reasonable lighting outdoors, we took all three phones out and about in Sequoia National Park in California, on both sunny and cloud days, and around Mountain View on an extremely sunny day. The 520 takes good photos and you wouldn't complain about them unless you saw them next to shots from the 720 — but the 720 is better. Colours are richer and more vibrant. Details are crisper and clearer. Plus the 720 has a slightly wider angle lens, so you get a little bit more in every photo. Both got excellent details for close-up shots in both strong light and shadow.
As you'd expect, the 920 takes even better photos with great lighting, crisp detail — in both distance and macro shots — and vivid, accurate colours. Contrast is better, so you can see more detail in dark areas, such as a burn scar on a sequoia trunk. Comparing the colour accuracy of the 520, 720 and 920 is interesting; when you look at photos from the 520 and 720 side by side, the 720 looks more accurate. A creamy yucca flower looks right on the 720 and too white on the 520. But when you look at all three together, you can see that the 520 does better on cool colours like the grey rock of a mountain; the 720 gives that a warm colouration that makes the rock a little too brown. But the 520 is too cool on more saturated colours like a bright blue sky or the deep greens of a forest, which the warmer effect of the 720 captures better. Sometimes the vivid colours of the 920 and 720 are almost too saturated; a shot of bright red flowers on a very sunny day came out better on the 520 without the depth of colour.
Indoors, in artificial light, on the automatic setting, without flash the 720 could wash colours out slightly (colours were more accurate with flash but the photo tended to look a little flat). The 520 had more vivid and accurate colours indoors, and excellent detail.
Although there are other Windows Phone manufacturers, Nokia is quickly becoming synonymous with the OS (and probably scaring off other phone makers). That means Nokia needs to have a handset for everyone. The Lumia range doesn't make it obvious which handset to choose, but if you dig into the details it does have a model to suit most people.
The Lumia 920 is a fantastic phone with a fantastic camera, with a price and weight to match; much as I love it, it's not for everyone. The 520 is a great all-round phone with a good all-round camera and nearly all of the advantages of Windows Phone at a remarkably low price. If you don't need flash and a front camera, it's a steal. The 720 is a great compromise between them, with a better camera than the 520 plus the option of wireless charging.
Which one should you pick? The one that suits what you want. For me, that's still the power and presence of the 920 (I honestly like the size and weight — the HTC 8x feels flimsy by comparison, which you can't say of the 520 or 720 either). But if I didn't have the budget for a 920, the 720 would be a great fallback.
If you want to see the full set of test photos from all three Lumia models, take a look at this set on Flickr.