Every one talks about MONOpoly, not DUOpoly, for a reason. But lets back up and just use the more generally used “anti-trust”. The law (in the US) is basically if you either a) collude with competitors to price-fix or restrict trade, or b) own so much of the market that your price is price fixing and there is no/little unrestricted trade, then you a violating anti-trust law. There is a similar intent in other places and the bar is placed higher or lower.

If you have the choice to buy phones which use one of several app stores, then you have choice in app stores. You also can’t install a Corvette engine in a Toyota Corolla but I don’t see everyone screaming about that. If you want a Corvette engine I do know the car you can chose in order to get it.

And yes, two non-colluding choices is choice. People aren’t suggesting that Apple and Google are all buddy buddy so there is choice. I suggest we all make one we are happy with and move on. =)

For the Corolla vs Corvette example, Toyota allows you to open the hood and take the toyota engine out. The screws are all standards and tools are available to get parts you need to take the engine out. If you had the tools to fit the Corvette engine in place, you are allowed to do it. You could build your own custom engine as well and put it there. We can put a lot of after market stuff in our cars, replace tires, wheels or even engine if we want to. WE own the car fully.

With the App Store case, they don't allow you to open the hood, unscrew and take out the apple app store and put an alternate app store. While Jailbreaking is legal, you need to use a hack to open up your iPhone and Apple actively plugs those holes in the next versions.

You are proving my point. I actually CAN install a Corvette engine in a Toyota Corolla (and it's been done), in fact I can install literally any engine I want. TOYOTA won't do it FOR me, but they'll let me do whatever I want because it's my car. I don't know why people such as yourself defend manufacturers from restricting what you can do with a device bought and paid for. It's not theirs, it's yours.

https://www.roadandtrack.com/car-culture/a30777891/ls1-v8-sw...

I'm not seeing how a market with 2 choices is dramatically more competitive than one.

You say people don't talk about duopolies, but they certainly talk about oligopolies.