S free iPhone 4s from apple locked

If you bought an unlocked (SIM free) iPhone direct from Apple, it stays unlocked forever. That's the whole point of buying an unlocked phone.

I was asking because I couldn't find the answer on the web and everywhere saidnthenfirst sim that goes into the phone locks to that network

" everywhere saidnthenfirst sim that goes into the phone locks to that network"

This has never been true.

Where did you read such a thing?

Various searches on google my friend thank you for the replies :)

That happens to phones purchased from Carphone Warehouse, not from Apple.