This week the Develop conference has been taking place in Brighton, and Sony have used the event to announce another bit of positive news about the functionality of the PS4.As was the case with the PS3, you can either purchase games on disc or via download. With the PS4 those two options remain, but Sony has confirmed any download games you have linked to your PSN account can be played on any PS4 console. What that means is, you can visit a friend, login to PSN on their console, and download and play your games.The other good news is, you won’t be waiting long for those games to download to your friend’s PS4 before you can start playing. Remember Sony’s “Play as you Download” feature? It will work in this situation, too. So only the first part of the game needs to be downloaded before you can start playing. The rest of the game continues to be pulled down in the background while you play.As games are linked to your PSN login, it means you could (if you trust them completely) share your login with a friend so they can check out the games you own. Sony will surely impose some form of limits, though, such as only allowing one console to be logged into an account at a time.This feature confirmation came via Neil Brown, Sony’s R&D senior team leader. He also explained that the Play as you Download feature isn’t just limited to downloaded content. It works with disc-based games, too. When you start playing a game on Blu-ray, data from the disc will be copied to your PS4’s hard drive in the background. That means load times should be cut significantly once the data transfer is complete.