Confused about the debate over Apple's locked-down ecosystem vs. Google Play or Windows Store's open--but potentially more hazardous--ecosystems?
Here's the deal:
Developers for apps must go through a laborious and slow process to develop an app or program for iOS or OS X. The app is reviewed by programmers at Apple, and may be denied permission to go on Apple's app store. Apple uses this process because it ensures a better user experience and ensures stability in the operating system (assuming Apple's programmers review the programs carefully, which they generally do).
However, this approach limits developers who may want to do something that Apple doesn't allow. It also limits a user's choice, as some reputable developers or companies do not release their app for iOS, due to the extra time and effort it takes to go through their screening process.
Microsoft, on the other hand, essentially didn't screen admissions to their app store, resulting in many buggy--or just plain dishonest--apps and programs. Microsoft is working on cleaning up this mess, but it's going to take time. Google strikes a pretty good balance with Android, as there are more apps on Google Play than there are on Apple Store or on Windows Store, and the majority of the apps for Android are useful and honest.
People often complain online about Apple's "locked-down ecosystem." It's essentially a philosophical complaint more than anything. Apple will restrict others' freedom in order to ensure that their products work well. Google and Microsoft allow a much greater degree of freedom for both developers and users, but the tradeoff is that users have to know a little bit about computers (and scammers!) to take advantage of that freedom.
Personally, I balk at someone telling me what I can and cannot do, particularly if they're trying to sell me really expensive stuff like Apple does. But there is a good argument to be made for Apple's procedure (for example, Microsoft's messy Windows Store. There's a good article about it here: http://www.engadget.com/2014/08/28/microsoft-explains-windows-store-crackdown/).
Okay, nerdy tech talk for the week complete.