(Pocket-lint) - Nokia made some nice high-end phones in years gone by, like, for example, the N95. But Nokia was never really about those phones, it was about affordable, reliable phones that everyone wanted to own, and that everyone could afford. There's not always money to be made at the top and bottom of the market, but if you can sell a lot of mid-range devices, you're likely to do well.

The Lumia 620 is something of a return to form. Removable covers, a sturdy feeling device, reasonable price and a solid operating system. It's all here, but with Nokia struggling to capture the market it used to dominate, does the 620 offer enough to lure people from those mid-range Android phones, or is it on a hiding to nothing?

We never understood the hysteria about interchangeable phone covers. Perhaps it's aimed at a demographic in which we do not belong. But they were a big deal on Nokias of old. And here, on the 620 they're back, to some extent.

Now, of course, covers are all about the back of your phone, because there's no front that isn't just screen. Nokia makes several different covers for the 620, but there's likely no end in sight for what third-party manufacturers will come up with. And, with the 820 Nokia has released 3D printing information, so customers can design and manufacture their own covers. It's only a matter of time before 620 owners can do the same.

READ: Nokia Lumia 820 review

What we love about the Nokia-supplied rear covers is that they have a two-tone free. This is most obvious on the lime green and yellow cover, where the outside is a fabulous bright green, but visible around the bezel is an inner yellow line. It looks top-notch and although green wouldn't be our first colour choice, it looks amazing.

Nokia sent us cases in white, bright blue, a pink and solid yellow. We liked them all, and they all cheer up the phone a great deal. Interestingly, all have a matte feel to them, except the lime green and yellow, which is very smooth and shiny.

As for the rest of the design, beyond the cover, it's all quite standard.

On the right-hand side, there is a button for controlling the volume, power button and a hardware camera button. The micro-USB is at the bottom, leaving the left-hand side free of controls and sockets. On the top, there's a headphone connection and slip off the cover and you'll find the removable battery, microSD card slot and micro-SIM tray. We like how the 620 handles your SIM - it sits in a pull-out metal holder - it's a much more sensible method than others we've used and feels much less likely to get caught with hand-cut SIM cards.

The speaker is concealed at the bottom right of the phone, on its rear case. Covers therefore need to have a hole of some kind to allow the sound out unimpeded.

Interestingly, the headphone jack also forms part of the case, it connects to the phone with some recessed connections. This is worrying because if you pop the back on and off a lot, it could stop the headphone jack from working. And second, anyone who does want to make third-party or 3D printed cases will need to include this, adding to the complexity.

The smallish screen was actually quite a surprise to us. At first glance, there's a little flicker and it looks like it might not be that good. But given a few moments during set-up - perhaps the coldness of the day and newness of the phone have a bearing - and things soon settled down. The screen is actually bright, more than bright enough to be seen outside, and reasonably detailed. We're not talking about high-end type resolution, but it's certainly good enough to use for any purpose.

Video looks great too. Fire up Netflix or any video app and you're looking at some really impressive quality within minutes. The screen also manages to control its brightness well - it's much less flighty in auto mode than most Android handsets we've seen and used.

Sound too, is an area in which the phone seems to punch above its weight. When it first rang, we were amazed by the amount of sound that came flooding out of the small speaker. It's loud enough to be heard in a busy room, or when tucked in your pocket. And when it comes to watching video, it's loud and clear too, so if you don't have headphones, or want to share with a friend - not on the N71 please - then that's an option too.

Via headphones, music sounded good, but not amazing. We flicked on Dolby Mobile though, and that seemed to improve the situation. Further improvements were to be had from tweaking the full EQ, and eventually we managed produce a sound that was very nice indeed. It might not be good out of the box, but there's certainly scope to get the sound you want from the 620.

We've written about Windows Phone 8 at length, so there's no point going over it all here again. Let's say though, that we're fans. This might not be an operating system awash with third-party apps, but the favourites are here and work as well, or better, than they do on Android.

There are quirks, of course, but these are mostly quite minor troubles. We noticed that contacts from Google would sometimes be a bit sketchy. One of our friends, for example, could be found via the phone portion of the handset, but not via the SMS bit. Once we tweaked the options in his number to be a "mobile" not landline, we could see him in the text messaging area. It's sort of obvious why that's happening, but it still doesn't make any real sense.

In terms of apps, there's pretty much everything you want, although some parts are dire. Games, for example, are still a bit of a mess. But there are games, and when you play them there's no difference to how they work on Android or iOS. We love the fact that there's a Netflix app - that's a big part of our video-based entertainment these days. Twitter has an official app, it's beyond hopeless. When we tried it, it wouldn't let us sign in because our phone's clock was "set to the wrong time zone". It wasn't, but the Twitter app would have none of it, and refused to work.

READ: Windows Phone 8 complete review

Aside from that, the things you really want to do with the phone can be done out of the box, for the most part. Email support is utterly brilliant, with Hotmail - or Outlook.com as it's becoming - Gmail and Exchange support all provided without any real need to configure settings. It has to be said too, you'll love the Windows Phone email interface. It's clear, crisp and makes a lot more sense on these phones than the equivalents do on Windows 8.

The built-in keyboard is really good too, and that's something that honestly surprised us with a phone this small. The correction seems to get it bang on, most of the time, and the keys, while small, don't seem very hard to hit. It's actually just about the best virtual keyboard we've used, honestly. And voice recognition is good - actually, really good. In fact, it's usable for replying to text messages it's that good.

Navigation is good through Nokia Maps. It's a little less easy to use than Google Navigation, and it never feels quite as slicks as Google's app. But there's traffic information and the usual map and satellite views, which make it a decent tool for getting around. We like that you can download maps too, for when you're not in the UK and don't want to pay for data. Oh, and don't forget to download a voice pack too, so the phone can yell instructions at you.

It's a bit confusing how Windows Phone handles SD cards. It turns out you can put music on your phone by simply chucking it on to a microSD card. Although the music app is, honestly, a little confusing and reluctant to tell you where it's sourcing its music. If you have an XBox music subscription, you can listen to lots of music while online. If not, then you'll be restricted to files on the phone or SD card.

If you're Windows 8 user, there's a "Windows Phone" app that allows you to copy data to and from the phone. It's a bit iTunes in some ways, as it also makes back-ups of your photos while you're syncing, which is nice. Music can be selected from your PC and synced via the app too, and it's both quick and easy to use, although it obfuscates what's going on, as is the current trend in Windows.

There's also Nokia Music, which is another way to get loads of free music. We love this service, and while it's somewhat limited, it's such a nice free benefit that it makes us smile every time we use it. Just as well there's Nokia Music though, because there's still no damn Spotify app. Boo!

When the phone detects a new SD card, it will also ask you if you'd like to use it for storing new photos and video. This is actually a very neat little feature, and we're pleased to see the phone using its brain, and asking logical questions, something that's all too rare in mobile devices.

The battery is our one area of real concern. It's a modest, 1300mAh pack, which we think will struggle to get you through a whole day, especially if you're using push email and surfing the web a lot.

The good news is that you can just plop it out, and shove a new one in if it does die. That won't suit everyone, and it's a massive faff, but it's a lot better than on most phones these days, with their absurd sealed-in cells.

We actually like the camera on the 620. It's not going to blow your socks off, but neither is it a disappointment. One of the things we like is that its modest megapixel count make images fairly small but the detail in them is good, colour natural and there is much less of that smooshyness you get in the fine detail on budget Android cameras.

Video at 720p is fine, especially for YouTube and Facebook. Detail isn't amazing but, we have to say, the autofocus is exceptionally good. It's both quiet and quick, and within a few seconds has a lock. It's also good in close up mode, so there's more to the video of the Lumia than perhaps we expected.

Verdict For anyone looking for the right Windows Phone to buy, we honestly think this is the handset for you. We loved pretty much everything about it - the battery is a concern though - and Windows Phone 8 is a more mature and enjoyable OS than any previous version of Windows on a phone. While Windows Phone gets some stick it's only when you spend any time using it that you realise it's a complete and competent mobile OS. Apps can be an issue, but if you honestly think about the software you use on your Android or iOS phone in any given day, it's a fair bet that Windows Phone has apps that do the same. Nokia is struggling right now, but phones like this have the skills to appeal to all manner of people. It's sensibly priced, while having more than enough hardware features to make it flexible and versatile. If you're looking for a good mid-range phone, this little Lumia deserves some real consideration.

Writing by Ian Morris.