How does free apps make money?

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Tags

1. #users
2. #access
3. #features
4. #version
5. #provided
6. #functionality
7. #download
8. #content
9. #premium
10. #through
11. #worth
12. #accessed
13. #committing
14. #freemium
15. #charge
16. #purchase
17. #purchases
18. #contain
19. #paying