Google’s improved Voice Search takes speech recognition to its next level: Google’s servers will now log up to two years of your voice commands in order to more precisely parse exactly what you’re saying.

In tests on the new app, which appeared in Google’s Android Market a week before Christmas, the app originally got about three out of five searches correct. After a few days, the ratio crept up to four out of five. Voice Search also doubles as a spoken-command system for the phone.

By storing hundreds, perhaps thousands of what speech recognition experts call “utterances” by the same person over months of use, Voice Search can better guess at what that particular person is saying. Voice Search digitizes the user’s input commands and sends them off to Google’s gargantuan server farms. There, the spoken words are broken down and compared both to statistical models of what words other people mean when they utter those syllables, plus a history of the user’s own voice commands, through which Google refines its matching algorithm for that particular voice.