That all depends on what illusions you have about how the market works. I would claim that a single app developer is still subject market concerns. Oftentimes developers are hired by bigger companies to do work, and in that case there is a typical "boss/worker" relationship, wherein they retain the right to fire you for any reason, or no reason whatsoever.
In short, what I would like to see is NOT a "professional association" (like Chamber of Commerce) that advances the interests of business, but rather a union that protects the rights of working people. The union would, ideally, ally itself with other organizations of working people to not just fight for our slice of the pie, but for every worker's slice.