In an update to the Google Search app for Android, you will now be able to perform searches even when your device is offline.
With this new feature, the app remembers your search queries for when it cannot connect to the internet. Later, when you are back online, it silently runs that query again for you and shows a notification with the results. Google says this feature doesn't require any additional battery or data than performing a normal search.
This should be convenient for those who live in spotty network coverage areas or while you're travelling and don't have consistent data connectivity.