Google Play Store and Monopolies
Success of smartphones OSes has always been determined by the app ecosystem it provides.
Users want a safe and convenient way to get new apps. Google and Apple succeeded because of the apps available for your average user. This power however has now led to a duopoly where Apple or Google are the judges who can make or break your app. (Android atleast allows for third party marketplaces like F-Droid for example. And at the end of the day, you could always side load apps)
There’s been an interesting discussion on HN today. As Apple and Google want a monopoly on payments - both of them tend to remove apps for in-app purchases bypassing the middleman and their 30% or so cut. (Understandable to an extent - apps could misuse such purchases)