Generator Research predicts 1.5 billion smartphone users by 2015
That's where market analysts can help; at least if you're prepared to spend the big bucks on their reports.
According to the latest from Generator Research, there will be 627 million smartphone users globally by the end of 2011, accounting for 12 percent of active SIMs.
By 2015, however, this figure will have risen to 1.5 billion smartphone users, or 25 percent of active SIMs.
In absolute terms, around 270 million smartphones are due to be sold in 2011, and by 2015 this figure will have almost doubled to around 450 million.
Get it while it's hot
The 280 page report contains 151 tables and 44 figures alluding to worldwide smartphone markets from 2011 to 2015.
Readers will be able to view quick data on penetration, installed base, unit shipments, average selling price and vendor revenues.
There's also detailed analysis of smartphone platforms Android, Apple, RIM, Symbian and Windows Phone as well as comparative analysis of the notebook, media tablet and netbook markets.
The report also boasts an additional analysis of the Nokia-Microsoft partnership.
"The most important recent development in the smartphone market has been the alliance between Nokia and Microsoft, announced in February.
"In a dramatic change of strategy, Nokia will phase out Symbian and de-emphasize MeeGo, while strongly adopting Microsoft Windows Phone for future smartphones," says a post on the Generator Research website.
"The key question is how well Nokia can manage the ramp-down of Symbian and the ramp-up of Windows Phone, in order to minimise the overall loss of market share."
The report will cost £249 ($400) for a single reader and £495 ($800) for an unlimited number.
If you're interested in picking up a copy or wish to see a full listing of contents, then visit the Generator Research website here.