Leaked low-resolution photos of the Nokia E75 first appeared in September last year, but it's taken a further seven months of development for the phone to finally hit the shelves. Has it been worth the wait?

The initial signs are encouraging - this is a great-looking phone. The form factor is candy bar with the bonus of a horizontal sliding Qwerty keyboard - reminiscent of the HTC S7. Thankfully, Nokia has solved the issue of bulk that affects most similar slide-out keyboard phones: the E75 is a svelte 14.4mm thick, so it's very pocket-friendly.

Nokia's E-series devices are usually notable for their build quality, and the E75 doesn't disappoint. It's solidly screwed together, and the materials used enhance the sturdy feel. The plastics don't feel as cheap as some competitors', and the metallic bits really are metal rather than metal-coloured plastic, including a stainless steel battery cover.

Where the phone's long gestation period shows is with its screen. Many recent smartphones have included high-resolution displays, but the E75's is just 240 x 320. In general that isn't a huge issue, but for web browsing some extra pixels would have been nice.

Connectivity is good, with 3G and HSDPA for when you're out and about, Wi-Fi for when you're near fixed infrastructure, and micro-USB for connecting to your PC. And, thankfully, Nokia has at long last realised that people like to charge their phones over USB, so when the device is tethered to your desktop or laptop its battery gets a top-up too.

Being a high-end Nokia, the phone uses the S60 OS, and here it's the third edition with Feature Pack 2 - so not the very latest version. But anyone who hasn't used an S60 phone for a couple of years will be pleasantly surprised - it's now a mature operating system and has gained some neat usability enhancements over recent years.

We really appreciated the dual mode feature, which allowed us to switch the device between work and personal modes.

The great attraction of the horizontal slider form factor is that the device works as well as a phone as it does for text messaging or email. And email is particularly well catered for on the E75, with support for the new consumer-friendly Nokia Messaging push service, or Mail for Exchange and Lotus Notes Traveler (yes, it only has one L) for corporate users.

Plus, of course, the phone has on-board support for connecting to POP3 and IMAP mailboxes. The only thing missing is BlackBerry Connect software.

Business users are well catered for, as alongside the great email support there's Quickoffice, which allows you to view and edit work documents, a PDF viewer, zip file management and Nokia's own mapping system, which uses the internal A-GPS receiver.

Until recently, high-end Nokia phones fell into one of two camps: the E series for enterprise use and the N series for entertainment. Any crossover was kept to a minimum, but with the E75 this is starting to change. Although it provides all the facilities that a corporate user needs, there's also a great music player (with 3.5mm headphone socket), both FM and internet radios, and - most surprisingly - support for N-Gage games.

There's also a 3.2-megapixel camera with autofocus, flash and VGA video capture. You wouldn't want to watch long videos on the small 2.4in screen, but apart from that Nokia has obviously designed this phone for both work and play.

The keyboard works well, and people with large fingers will find it a lot easier to use the E75 than phones with front-mounted thumb-boards. Spacing is good, and frequently used keys such as "@" are available with a single key press. The only minor issue we had was the awkward placing of the Shift key, but we soon got used to it.

And, despite the fact that the phone has a small 1000mAh battery, we were impressed with how long it lasted. Our real-world test consists of a half-hour phone call, a 50MB download, and then running the phone accessing a POP3 mail account every 30 minutes over an HSDPA connection until the battery dies - and the E75 performed better than any other phone we've seen.

It ran for an astonishing 179 hours (more than seven days) before giving up the ghost. Although this is a relatively light-use scenario, it's fair to assume you'll get a good few days' more intense use out of it before having to recharge.

With the E75, Nokia has thrown most of its business and consumer toys into one neatly styled package, and to great effect. The form factor means that it doesn't have a big touchscreen like the HTC Touch HD or iPhone, but despite that it's a very usable phone, and one that neatly bridges the worlds of business and personal use.