In brief
The article argues that one-time app pricing can survive through steady new-user growth. Subscriptions may increase revenue from existing users, but risk shrinking the user base without solving the underlying growth problem.
Generally, after developing an app，, developers sell it for a one-time fee. This is a very simple business model, and customers like it. Once they pay to buy the app, they do not need to pay renewal fees later. It seems a fair deal for both customers and developers.
However, many software publishers later switched to a paid subscription model. The usual argument is that modern apps are not static: developers need to keep fixing bugs and adding new features. If people keep using a piece of software, it seems only fair that they should keep paying. Providing updates to users who have paid only once feels somewhat hard to accept.
How can a business survive with a one-time paid app model?
The secret is growth. If an app attracts new users every day, those new users will pay for the app. Providing updates to existing users does not cost much either. So why are other companies so eager to adopt a paid subscription model? Because they have stagnated. They have little appetite for growth, since the users who need their software are already using it, and paid updates do not work. As a result, the only way for these companies to increase revenue is to charge existing users more.
The only thing that is hard to understand is why small companies also want to adopt a paid subscription model. Are they also facing stagnant growth in their user base and hoping to improve their bottom line? If so, they are finished—subscription fees will only shrink their user base further, leaving the underlying problem of insufficient user growth unresolved.
http://www.hksilicon.com/articles/1058812