Why is iOS closed source?

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Tags

1. #system
2. #closed
3. #customize
4. #something
5. #store
6. #seems
7. #google
8. #apple
9. #source
10. #things
11. #operating
12. #there
13. #agree
14. #everything
15. #allows
16. #android
17. #tweak
18. #means