Apple will have no choice but to open its devices to application stores other than the official one, but that does not mean that it will lose control over them, because will continue to charge and review the apps.
The new European directive on the digital market (DMA) forces Apple to allow the installation of applications from sites other than its official app store, with a deadline that ends next March, and that seeks to end the "monopoly" from Apple on iOS. This has opened up all kinds of speculation, ranging from "anything goes" to those who think that this is going to be like Android and will allow you to install any app store that you can download from the internet, even those of us who think that Apple will continue to have tight control over what we can install on our devices. And the latest rumor mill assures that this last position is the one that will most closely align with reality.
Applications may be installed from stores outside the App Store, that is inevitable, but The applications will still have to go through a review process by Apple, and the company also plans to charge commissions in these external stores. We do not know if they will be commissions in the form of a % of sales, or a fixed rate for being able to install applications on the iPhone and iPad. At least this is the idea they have in Cupertino, and I have no doubt that it will be how this new era without a "monopoly" begins. What I also have no doubt about is that the European Commission will require new measures that seek to reduce Apple's control over its devices. These measures will currently only have an effect on the European market, although they may end up forcing the United States to do something similar sooner rather than later.