Another example of this is the myriad of apps which provide a native app front end to the Google Reader service. Google recently announced that Google Reader will be shut down on July 1st, 2013. Many of these apps will die off because they don’t offer any content or functionality of their own. Others, like Feedly and Reeder (and many others, I’m sure) have a roadmap in place for how their product will live on after Google Reader is gone.
I don’t mean to say anything positive or negative about building a product that is so dependent on another company’s service, but it’s definitely a risky thing. For some, it’s a risk that was not planned for, and that’s unfortunate.