sharlene's dashboard

I have an iphone 3gs, i bought the apps via the phone, ie downloaded on the iphone through app stores, but when i attach phone onto laptop, only can see my own songs downloaded etc, for ipod, cannot see any apps, then when i take the phone off the laptop, none of the apps work, but they are still on the phone, then I have to reload one, or buy a new game etc, then it all works again, but next time I hook the phone to the laptop and go onto itunes same thing. My library does not even show applications anywhere in itunes, how is that possible. I cannot even access applications via itunes in other words. People have said I must go back to service provider, I think they might know even less on this. Also do I have to backup and restore, is that the only way this will sort itself out. I did update to 3.01 version of iphone, could it be that, ,that caused the problem, have read some people saying this as well.

Please help.