• by Gavin O'Malley , Staff Writer @mp_gavin, September 15, 2016

Think Snapchat's popularity is peaking? Think again. The creative messaging app is poised for at least two more years of double-digit growth, according to a forecast from eMarketer.

Year-over-year, the app's monthly active users will increase 27.2% this year, and then 13.6% next year.

From 2018 forward, Snapchat's annual audience growth will fall into the single digits -- but in the world of social-centric messaging apps, that's a long way off.

What's Snapchat's secret? Critically, “we encourage creativity,” Bryan Kim, manager of Snapchat's strategy group, tells eMarketer. Of course, that's thanks to the app's various doodles, geofilters, stickers and lenses.

All told, eMarketer projects 58.6 million U.S. consumers will use Snapchat at least once per month this year. If accurate, that will represent 28.3% of U.S. smartphone users, and 18.1% of the total U.S. population.

Both of these percentages would be a considerable gain from two years ago, when Snapchat was used regularly by just 10.3% of U.S. consumers, and less than 20% of U.S. smartphone users.

As it continues to scale, of course, Snapchat's usership boom is increasingly behind it. I'm talking about 2014 and 2015, when it saw annual growth rates of 83.9% and 40.7%, respectively.

Also of note, Millennials still make up the largest share of Snapchat's U.S. user base, totaling 40.9 million -- or 70% of its monthly active users in 2016 -- eMarketer estimates.

Going forward, Millennials will remain in the majority, but their share of the total Snapchat audience will shrink each year as the app's appeal increases among other generations.

By the end of 2020, eMarketer predicts that Millennials will make up 56% of all U.S. Snapchat users.

This column was previously published in Moblog on August 29, 2016.