Three has recently launched the new MiFi E585 Wi-Fi modem, replacing the E5830 as iPad users' must-have accessory.

MiFi devices take a 3G signal in and share it through their own Wi-Fi network, allowing phones and laptops to share a single connection.

However, it's with iPads that the MiFi E585 really comes to the fore, as it can replace the need to pay more for a 3G version of Apple's tablet, saving you a lot of cash in the process.

The new E585 offers one-button start up, an LED display showing network stats, up time and battery life, and up to four hours of continuous use.

E585 from three

In the box

The modem comes with a wall charger, two USB cables – one long, one short – a SIM card and nine double-sided 'help cards', as well as all the usual paperwork and instructions you'd expect.

If you're not familiar with MiFi devices then you'll be surprised by how small and compact these modems are. Weighing just 90 grams, the E585 fits in the palm of your hand and feels sturdy enough to be thrown into your bag and left to do its thing.

There's a power button on the right hand side which glows green when in use. One long press of this turns the modem on and off, and a short press turns the screen on when the device is idling.

Power button

At the bottom there's a micro USB port for charging and there's a covered MicroSD card slot on the left edge.

Once the battery and SIM card are installed behind the removable plastic cover you're ready to go. Hit the power button and the E585 boots up, connects to the Three network over 3G - or HSDPA where available - and opens its own encrypted Wi-Fi network.

The whole boot up process takes about 45 seconds, and then you're up and running.

MicroSD slot

While the E585 comes encrypted, you can change the password and network name to anything you want.

And for any forgetful users, these details can be reset to default by holding the restore button hidden beneath the cover.

When up and running, the modem works just like any other Wi-Fi network you've ever used.

Screen

Up to five devices can be connected to the hotspot at any one time and we found no problems with browsing on an iPad and smartphone simultaneously.

The E585 goes to sleep while inactive and wakes up as soon as a connected device requires an internet connection. As a result, emails were pushed to our iPad as quickly as using a regular broadband connection.