Mitac Mio 558

  • Editors' rating
    8.0 Excellent


  • Wi-Fi and Bluetooth built-in
  • SD and CompactFlash card slots
  • replaceable battery


  • Battery life could be better

Mitac is beginning to set itself up as quite a player in the Pocket PC area. It has two existing products under its Mio brand, the 338 and 339 at the lower end of the price scale, and two new products: the Mio 558, reviewed here, and the Mio 168 (the first Pocket PC to include a GPS receiver), which we will review shortly. The Mio 558 is a well-specified business-orientated handheld, sold at an attractive price (£344.99 inc. VAT) by Evesham, among others.

The Mio 558 is a nicely designed device. Its overall dimensions are close to the average, at 7.2cm wide by 12.4cm high by and 1.53cm deep: the height is a little over the average, but the weight, at 170g, is reasonable. A key factor here is the use of plastic rather than metal for the casing, which is as robust as any we’ve seen using this choice of material. The hardware design is generally conventional, although there are some subtle innovations. For example, the four application shortcut buttons that sit in standard formation below the screen are bevelled slightly, making them easier to find. The navigation button is in its expected position too, but is a tiny joystick rather than a pad. It's reasonably easy to use, but doesn't allow for diagonal movement. If the joystick is not to your liking, there is an alternative in the shape of a scroll dial on the left edge of the casing. This is rather more robust than some we have tried, and is nicely indented to help prevent its accidental use. The same degree of thought has not been put into the record button that sits beneath it. As with many other Pocket PC devices, it's all too easy for this to be held down accidentally while the Mio 558 is in a pocket or bag, resulting in nothing more than a run-down battery. The protective case is no help here, as it leaves both the scroll dial and record button free. Mitac has done well to position the headphone jack on the top of the case. This is the most ergonomic position for it, although the jack itself is the smaller 2.5mm type so you’ll need a converter to use high-quality headphones. The speaker sits on the bottom right of the fascia, and is offset visually by the power switch on the left. The stylus sits in a housing on the back right of the device, and is an extending type. It's well weighted, has a relatively large circumference, and is among the best we’ve seen.

The Mio 558 boasts an impressive array of features. The processor is Intel’s PXA263 running at 400MHz. There is 64MB of RAM, some of which needs to be set aside for running applications, plus 64MB of flash ROM of which 32MB was available for use on our review system. Both Bluetooth and Wi-Fi (802.11b) are built in: two LEDs on the upper right-hand side of the case deliver a range of functions, one of which is a steady green glow if a wireless connection is active. Both wireless modes can be turned on and off via an icon on the Today screen. This icon also lets you activate ‘the USB Dongle’ mode -- a clever function whereby the Mio 558 can act as a wireless adapter for non-connected computers. To use this, you need to make a USB connection from the Mio 558 to your computer (Mitac provides a converter from the Mini-USB connector on the underside of the Mio’s case, but not the cable itself), and install a driver on the PC. It’s a clever add-on that could prove useful in a range of home and office situations. The Mio 558 has both SD/MMC and CompactFlash card expansion slots, and supports SDIO. This is the kind of expansion slot configuration we like, as it allows the maximum use to be made of any cards you may own, the freedom to shop around for best-value peripherals, and the chance to permanently dedicate a slot to backup, leaving the other free for memory or add-ons. Mitac’s software bundle is small. The Mio Utility lets you change the processor speed to help boost battery performance, format the user area of flash memory, and -- in this particular model -- choose between various wireless connectivity management settings to help prolong battery life. eBackup is a simple utility for sending backups to either the flash memory or an external card. It doesn’t automatically backup when power gets low, but you can choose precisely what you want to save. eViewer is an image viewer with the ability to annotate images with text or drawings. It isn’t a vast software bundle, but it’s better than nothing. The Li-ion battery is removable, and there's space in the supplied docking cradle to charge a spare.

The Mio 558 is notable for its dual wireless connections and twin expansion slots. Added bonuses are the excellent Today-screen-based wireless controls, generous flash memory and the removable battery, which should allow you to prolong the Mio 558’s useful life in the field. Mitac claims 10 hours' typical life for the removable Li-ion battery without wireless turned on. Our test, which involved looping MP3s with the screen always on, wireless off and the Mio Utility configured to ‘Auto’ (to help slow the processor down and conserve battery power), resulted in music playback for 2 hours and 49 minutes, and total battery life of 3 hours and 45 minutes. This is clearly well short of Mitac’s claim, and a little disappointing. We had no problem establishing connections over Wi-Fi or Bluetooth, and we appreciate the way you can configure the wireless module to turn itself off when the device powers down by choosing Deep Power Mode in the Mio Utility. We like the Mio 558. Our main gripe is the memory complement: 64MB of RAM divided between storage and program memory, plus 32MB of available flash is not ungenerous, but where on-board storage is concerned, more is definitely better, and 128MB of RAM would suit the otherwise generous specifications of this handheld.