If you and your friend BOTH have the Galaxy S and are both on the same carrier, but are seeing different search results, I can only give two reasons why you and your friend receive different search results.
1. You are typing a slightly different search query than what your friend is. If I am wrong and you are typing the exact same query, but coming up with different results, then I can only imagine one answer.
2. Your Android OS. If your phone is running Android 2.1 and your friend's is running Android 2.2, your friend will get more app displayed. Some apps are developed to only work on Android 2.2 or greater, so a phone only running Android 2.1 will not see the apps displayed in it's Market.
Samsung Galaxy S handsets in the UK and elsewhere are currently in the process of being updated to Android 2.2. Not every phone gets updated at the same time, so it is very likely that your friend's phone was updated in the last few days to Android 2.2, but that your phone has not received the update yet.
I would ask your friend to tell you what version of Android they are running, as that will give us the answer.
In addition, your update to Android 2.2 should be coming soon. It may even have already been available for your phone. Install Samsung Kies and have the software look for an update for your phone. If there is one available, install it and then compare the app search results again. Let me know how everything goes.
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