[General Topics] Menneisyys:
Instant messaging is one of the key features of today’s communication. It’s much faster than e-mailing, much easier than picking up (and, probably, paying for) the phone and is pretty reliable.

E-mails, even if they are delivered at once (which isn’t guaranteed) are not guaranteed to notify the user at once (see for example this excellent article (and some feedback here) from the Modern Nomads folks on this question). Not so with instant messages – they, unless the connection is lost and the sender doesn’t notice this or, if it’s using a central dispatching server and it’s heavily overloaded (more on these problems later), promise really instant message delivery and notification.

You may have been a long-time user of desktop-based instant messaging solutions like MSN / Live Messenger, AIM, Yahoo, Google Talk, IRC or ICQ. You may also have a Jabber client – either just for fun (on at, say, the central Jabber server) or at your enterprise, where Jabber is a decent alternative (also see this article and “Google Talk might be(come) the right tool for your corporate”) to other enterprise-grade instant messaging & presence solutions like IBM Lotus Instant Messaging and Web Conferencing, Microsoft Office Live Communications Server and Novell GroupWise Messenger – and, to my knowledge, the one and only platform directly supported by Windows Mobile.

Fortunately, most of these services are also accessible on Windows Mobile. Note that I won't introduce these services here at all. If you're a newcomer to instant messaging (IM for short) and would like to choose one of them, which one you go for is mostly a matter of personal taste and the number of your friends using the given service.

The latter is because there is little interoperability between the different services. That is, if you install, say, the ICQ client, you won't be able to talk to your buddies using MSN (Microsoft) clients and so on. On the desktop, this can be easily combated by going straight for multi-service clients like Trillian or, if you need an open-source implementation for your Un*x desktop or mobile (and even desktop Windows!), Gaim (see here the Qtopia version of Gaim, should you want to use it on your Linux-based, even originally Windows Mobile-based mobile). Unfortunately, there’s no direct port of these two well-known, hugely popular clients to Windows Mobile. As far as Trillian is concerned, however, Web clients are already supported), which, however, are far more awkward to be used from a mobile.

Personally, as far as selecting the best service for your needs, I mostly recommend MSN because its support is definitely the best on Windows Mobile, should you want to go for a messaging platform without being constrained by the services your existing buddies are already using. Not only all third-party clients do support it (except for one-protocol ones like PocketICQ, gsICQ or the three-service mChat), but also Microsoft's own IM solution, MSN Messenger and Live Messenger, are very solid and, with MSN Messenger, in general, built-in products. Being built-in means you don't need to install (and, in cases, pay for) third-party software on your Windows Mobile (WM for short) device but use the one already available in there. What I also recommend if you’re looking for a messaging platform but, for some reason, don’t want to go for the MSN service is either Jabber or ICQ. Both have excellent Pocket PC clients – for example, the former is supported by almost all major titles and latter is supported by two of the best and, what is more, free titles, mChat and gsICQ.

You may also want to consider for example whether you need HTTP tunneling when going for a particular service. This isn’t supported by some services (for example IRC); the more recent ones like Jabber, ICQ, Yahoo and MSN, however, already support it (see for example the “Jabber and HTTP” section here and this for more info on the two latter services). Also see the comparison chart in the Comparison of instant messaging protocols for additional information.

In general, all IM solutions offer almost the same capabilities: in addition to chatting, file transfer, some even support video / audio chatting, multi-user chat (groupchat) and styled text. In addition, as far as Windows Mobile-compliance is concerned, Jabber servers are perfectly suited for enterprise-grade deploying. Please see this page for more info & links to individual Jabber server products, should you want to choose and, then, set up one for your enterprise, keeping Windows Mobile-compliance in mind.

Now that we have a generic picture of what IM services there are, we can move on to the clients that are actually able to connect to these services.

Fortunately, there are several Windows Mobile instant messaging clients. No matter what protocol (service) your mates use, you will be able to find at least one (and, in most cases, several) applications to do the task. With most of these applications, all you need to do is pretty straightforward: you supply them the login / password credentials to your (preferred) service and simply log in. With some of them (most importantly, imov Messenger), you will also need to use another central server account (which you can register from inside the app), which makes the life of a complete newbie a bit harder at first but soon becomes pretty easy. That’s because you can create /register the account right from your IM app on your Windows Mobile device.