Can I update my unlocked iPhone?

I have an unlocked iPhone 4 that isn't jailbroken but I'm using simple mobile can i still update or will it get bricked. Please answer correctly I don't want to risk the phone I just got.

If its not jailbroken then most likely the phone is factory unlocked. Technically, you should be able to update without loosing the unlock based on my experience with customers.

You can update it

If it was unlocked by Apple (meaning you purchased it from Apple already unlocked) you can update it. If it was not unlocked by Apple I would not risk it if I were you.