Mio, however, has been brave enough to step up to the plate with the DigiWalker A501. It brings all the features of a GPS unit, phone and PDA together in a single device that will set you back around £320 SIM-free.
Most of Mio's sat-nav devices are powered by Windows Mobile technology, so it's no surprise that Mio has chosen Windows Mobile 5.0 for the A501's operating system. It's also added a few extras on top including its Mio Menu, which is launched via a dedicated button on the front. This presents you with a screen full of large icons giving you quick access to applications such as the sat-nav software, media player and Web browser.
Although the menus in the navigation software aren't as well laid-out as they could be, the actual maps are very easy to read and the audio instructions are clear and precise. However, if you miss a turn, the device is sluggish in re-calculating a route to get you back on track.
The A501 performs pretty well as a phone. We had no problems with reception and the call quality was always top class, as the built-in speaker sounds great in both normal and speakerphone mode. The battery life was also good by the standards of most smartphones. It's got enough juice to cope with 4 hours 30 minutes of talk time, and it'll keep running on standby for around 8 days.
Naturally, you get all the usual features you'd expect from a Windows Mobile device, including Pocket Word, Excel and PowerPoint, plus Windows Media Player. For storing files there's around 175MB of free memory, but naturally you can add to this using the SD card. The slot is taken by a 1GB memory card containing the mapping data for the GPS software, however, so you may end up having to juggle cards if you've got lots of your own files to store.
The designers must have been on holiday when the A501 was developed, because it's one of the ugliest devices we've seen for a while. The plasticky exterior doesn't help its cause, but really it's the stubby and chunky dimensions that are the real killer. Design-wise, it sits in the no-man's land between a PDA, a sat-nav and a phone. It's too stubby to feel like a phone, too small to feel like a PDA and is too fat to fool you into thinking it's a sat-nav.
More worryingly, the device also feels underpowered. The 200MHz Texas Instruments OMAP processor just doesn't seem to have the poke to keep everything ticking over at a decent speed. It's slow at route re-calculations and screen updates also tend to be sluggish. In fact, the screen isn't great, as it's quite small and overly reflective, making it difficult to view in direct sunlight, even with the brightness turned up to the max.
Also, although the phone is quad band and has Bluetooth onboard, there's no 3G or Wi-Fi support. As a result you're limited to GPRS speeds when using the Web browser and this feels very slow in this day and age.
Full marks to Mio for trying, but the A501, at around £320 SIM-free, is a disappointing attempt at shoehorning a sat-nav, phone and PDA into a single device. Its sluggish performance, ugly design and lack of 3G and Wi-Fi support will leave most people cold. If you're after a device that has similar functionality we'd advise you to take a look at Nokia's N95 instead.
Edited by Jason Jenkins
Additional editing by Jon Squire