Freedom of association is not explicit in the first amendment but it is still widely understood, and tested in court that it protected by it. Financial transactions between two individuals or corporations is an exercise in free association. Nobody is forcing anyone to buy an iPhone.
* Apple makes a phone, it works in X, Y, Z ways and asks someone to buy it. <- this is what people call "speech" for a corporation.
* Someone says, ok - I will buy this. <- spending money in a consensual transaction is considered a form of speech. This is well established in American law.
* Government later comes in and says - hey, you MUST provide feature A, even though Apple doesn't want to. <- this violates the "congress shall make NO law prohibiting the free exercise theoreof" of the "free speech" portion of the first amendment.
It's also an infringement on the first amendment right of the customer to engage in a consensual transaction with Apple as now the government is forcing them to pay for and use something that they did not agree to in said transaction.
Apple is not being deceptive about how their walled garden works. If they were, then it's just fraud.
Anti-trust in and of itself is an infringement of the first amendment, and is often counterproductive to the intended goal anyway. How did getting slapped with Antitrust work out for Microsoft? They are bigger and more powerful than ever, and they still ship two web browsers with their operating system, and nag you when you try to change it. Standard Oil got splintered and Exxon came out of it. Many such cases.
