The worldwide success of RIM's BlackBerry means many staff have mobile access to email. This has improved productivity but has also had a few less desirable effects: BlackBerry addiction is a real problem, hence the references to " CrackBerry" and so on. Nevertheless, the benefits for businesses vastly outweigh the drawbacks, so mobile email is here to stay.

Of course, the number of products that can provide remote access capabilities has grown, so companies have a lot of options to consider. The choice is made more difficult by some other factors – for instance, the continuing litigation between RIM and patent farmer NTP in the US has made customers worry about possible interruptions to service and roaming difficulties.

Microsoft entered the market last year and is collaborating with Vodafone to provide push email services based on Exchange Server 2003 and Windows Mobile devices. Nokia has also been active – it announced a range of products in October to support no fewer than six email protocols, a list that includes the BlackBerry system but not the Microsoft one.

Apart from Microsoft and RIM, at least four companies produce their own push email systems for mobiles. The ones I know are Good Technology, Nokia, Seven and Visto. In addition, DataViz supports the Microsoft scheme in its RoadSync product, which works on Symbian and Palm platforms. There has also been some consolidation in the market; Seven acquired Smartner, which had already bought Commtag.

Let's take a look at what's involved in choosing a mobile email system. Managers should start the selection process by checking that the products support the corporate email system. All support Exchange Server (but check the version) and most will handle Lotus Domino. If you look hard you can also find support for conventional POP3 or Imap.

It is preferable that the mobile software should run on as wide a range of mobiles as possible and certainly the ones owned by the company. Most software runs on the various Symbian platforms but there is also support for Windows Mobile, Palm and Brew to consider. Some products can provide a basic system using the Java facilities on most handsets.

Once that's all sorted out, you have to be sure that the mobile network will provide the data services needed both at home and when roaming in those countries where employees travel. If the preferred network is a 3G one you also have to check that the mobile can use 2G networks where there is no 3G coverage.

So, having got all the compatibility stuff out of the way, one can then compare the features provided by the various products and their purchase and operating costs. Don't ignore the running costs, because most networks don't offer a flat-rate data tariff, which can lead to loud noises from the chief financial officer if users go above their included transfer limits. I never said it was easy – but the rewards for making the right choices are high.