I am running android 2.3.4 and also have this. It is only visible on google play. My apps . Then it's not showing in installed tab, but if you scroll sideways to all apps (which shows everything you ever downloaded) it's there. Called testapps with no thumb, only android symbol. If you click on that you can rate and review. There is a lengthy discussion from xperia play users who are very confused about this. If you click open button at top of page it loads, the preinstalled game Tetris.
WTF IS THIS.
You can only remove if you root your phone.
People think there is a conspiracy between Sony and Google because no one is answering any questions.