I write a lot about targeted marketing - which means effecting messaging your users at the right moment and in the right place. I use the term "in the river marketing" to describe it. Here is a great example by Flipboard - a master at mobile design. Flipboard - which has huge distribution as an iPad app - is trying to promote their new iPhone app (which generally is a different experience and design). To do that, Flipboard gets as "in the river" as possible. The welcome screen generally displays a story from your network. In this case, it is a note directly from Flipboard's CEO Mike McCue and describes their new iPhone app. This ensures that all Flipboard users see the message and, at the very least, recognize that Flipboard now exists for iPhone. That's aggressive. But it's targeted: these are Flipboard users and iPad owners (so they likely have iPhones as well).
The major question that mobile publishers / developers struggle with: how do you then drive conversion? What next after this message? Driving downloads across device is difficult. Driving downloads from the web is even harder. Then layer on tracking to understand the efficacy of the campaign and it's unfortunately very difficult...
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