Why do iPhones slow down after 2 years?

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Tags

1. #intentionally
2. #reason
3. #start
4. #older
5. #nature
6. #there
7. #lithium
8. #charge
9. #apple
10. #degrade
11. #batteries
12. #slowing
13. #iphones
14. #storing
15. #their
16. #slows
17. #after