Smartphone penetration in North America and Europe — in combination with continued mobile growth in Asia, the Middle East, and the rest of the developing world — has resulted in a robust conversation about mobile marketing opportunities.

And the conversation is not just limited to the media and advertising industries.

Marketers around the globe are rubbing their hands with excitement about new communications and sales channels and their potential revenue.

It’s estimated there are more than 6.8 billion mobile-cellular subscriptions worldwide – almost as many mobile-cellular subscriptions as people in the world, with more than half in the Asia-Pacific region.

While annual growth has slowed as mobile penetration has increased, marketers cannot ignore that in certain parts of the world the mobile “screen” is becoming the primary source for news, entertainment, and commerce.

People are talking about “screen marketing” – as in mobile phone, tablet, computer monitor, and television/cable. While the raw potential is exciting, the universal truths of permission-based marketing should serve as a caveat for any marketer building audience or advertising revenue forecasts.

The Mobile Marketing Association views permission-based mobile marketing as a “separate and distinct” part of mobile marketing. The MMA defines permission-based mobile marketing as “the practice of gaining consent from consumers in advance of a continuing marketing dialogue taking place on mobile devices and in return for some kind of value exchange.”

Truth is, permission-based marketing is the same, regardless of screen or communications channel. And some would argue that permission-based marketing is a key ingredient to mobile marketing effectiveness and should not be viewed as a “separate and distinct” part of mobile marketing.

When AT&T introduced its “shop alerts” geographic-based text messaging services in select markets in the northeastern United States back in 2011, it was designed as a service “through which companies can send text messages to users who choose to receive special offers.”

While geographic-based mobile marketing takes advantage of the smartphone’s GPS location services, the key to effectiveness is user permission. As consumers, we expect certain communications channels to include non-solicited commercial messages (think TV/cable).

When those unsolicited commercial messages appear across other channels (e-mail, text, flyers under auto windshield wipers), the response – and the results – are mixed at best.

Imagine someone living in a metropolitan area walking down the street and having their mobile device vibrating or ringing with every unsolicited commercial text message as they pass each retail location.

While attitudes and expectations about unsolicited commercial messages vary by communications channel, they also vary by audience segment and region of the world. A recent eMarketer article concluded that North American mothers “want to be the ones who initiate commerce-related activities in today’s digital environments.”

Cited in the same article, research from Arbitron and Edison Research found that 25% (of moms) use daily deals sites (permission-based), compared to 14% of adults in general.

While mobile devices have become “smart,” consumers’ expectations for how and why they use their mobile device vary dramatically based on demographics (old versus young) and geography (New Delhi versus New York).

To some, their mobile device is a multi-functional appliance that serves their personal information needs. To others, their mobile device is just a phone.

While consumer attitudes and perceptions will evolve over time, marketers should manage their expectations for mobile marketing with a healthy dose of the principles behind permission-based marketing.