Earlier this week, Ulster Bank announced that it launched the first free mobile banking app in Ireland for the iPhone. The bank follows many other European banks that have jumped on the iPhone app bandwagon in the past 18 months.

In a report titled "The State Of Mobile Banking In Europe: 2010" that I published earlier this year, I argued that thanks to its large-screen, touch-screen interface, the app store, and the fact that it mostly comes with fast all-you-can-eat data plans, it opened many people’s eyes for the potential of the mobile channel. In fact, iPhone users are about three times as likely to use mobile banking as other mobile phone users.

Of the 42 largest banks in the UK, Germany, France, Italy, Spain, the Netherlands, and Sweden, as many as 28 now offer iPhone banking apps — a whopping 67%. Although their launch has generated a lot of free PR, these iPhone apps have limited reach today. According to Forrester’s Consumer Technographics data, only about 2% of European mobile phone users have an iPhone and no individual country exceeds 4% adoption.

To reach more customers, many banks are launching apps for other platforms these days. So far, 12 out of the 42 European banks we reviewed offer apps for Android (29%). But only two banks (5%) — Spain’s la Caixa and Germany’s Sparkasse — can be found on RIM’s BlackBerry App World.

This is suprising since despite the weak mobile browsing experience compared with iPhone and Android, BlackBerry users are very likely to access their bank accounts via their mobile browser. In fact, they are nearly as likely as iPhone users to access mobile banking Web sites and even more likely to receive SMS alerts. Mobile banking apps for BlackBerry that deliver a compelling user experience would thus have a large potential user base.

BlackBerry users and users of mobile banking apps show comparable demographic profiles: 1) They tend to be younger than the average population —BlackBerry devices are particularly popular among young consumers because of their strong SMS and instant messaging capabilities. 2) Mobile banking app users are more likely to have high incomes — which is in line with BlackBerry's strong footprint among corporate email users.

Thanks to this match in target audience, more banks should put BlackBerry mobile banking apps on top of their development queue.