Limit on apps?

Hallo. I would like to know if there is a limit on how many pages I can have on my iphone 3G. Is there a limit of 10 pages plus the original one? Because I have 3GB free memory on my iphone but if I download many apps that need more than 10 pages on the iphone they are installed but I can't see them. Is there a limit or does my iphone have a problem? Thanks.........