Google has come out with a new search feature called In Apps. It basically does a search on your phone. It is a kind of an Internal search.
One could search for messages which had some particular content you were looking for. Suppose you were chatting with someone a month ago about a restaurant and you don’t remember the name. In this case you could just search for “restaurant”, and it would search for all the messages which has that word.
Keep in mind that the data remains private and it is with you only. Unlike the regular Google Searches which take place in a server somewhere in the world, this search is done Internal within your phone and the data doesn’t get transmitted outside
In order to use this feature goto https://www.google.com. Then in the Menu where you find Books, Shopping , Images etc. Navigate to the right until you find “In Apps”. Then type in the words you want to search and hit the search button. It would then give you the results. The results currently work for you messages and Google Apps like GMail.
Please note that this is currently available in Android only.