Can an iphone be permanently unlocked?

Actually i want to buy an iphone in India. Is the iphone 4s or 5 which i buy in India unlocked or jailbreaked? I heard that the cost of the phone in other countries is lesser than in India…

my frnd bought a phone from US and said that it is already unlocked if he updates his OS now will the phone will be locked again? So here i don't understand that can an iphone will be permanently unlocked ir can i use it anywhere in any other country? Can i update the phone? Will it be locked again?

Purchase an iPhone which is unlocked from any country and it wil work everywhere in the world… U wil be able to update it… Trust me