Google’s Android market gets an update 3.1.3, which packs minor changes and additions of features. New features includes Google’s +1 button on apps and a PIN lock.
As in the web, now you can +1 the app you like from the market. Another feature PIN lock seems to be pretty good in order to avoid accidental paid app downloads. You can easily set a PIN number to your account and for each buy from the Android Market you have to enter the PIN number.