“Google mobile” app for iPhone and iPod touch is now replaced by “Google search” which also has a new look and added features.

Features of “Google Search” for iPhone and iPod touch

Redesigned home screen which lets you swipe down to see the search bar while searching.
Apps button on the home screen lets you access other Google apps.
Swipe left to right to use the toolbar that lets you search by specific categories like images, news etc..
Swipe down to view previously searched results and Google settings.
Updates for Google Goggles, Voice Search, Search with My Location and Gmail unread counts.

A demo video of Google apps for iOS from Google: