How do I maintain records when updating my game?

After updating my game on the market, how do i do to keep the records of the people who have played my game where they are?

I dont know if this is the best approach, but lets say you are using webstorage to store their progress.

At the beginning of the game, add in a check to see if your webstorage keys exist, and if so, load those high scores etc.

So even if they install a new version it will check to see if they have played before and simply start with those scores for the high score table etc.