Apps have disappeard Yesterday morning when I woke up I turned on my smartphone and I saw that all my application have disappeared!

When I entered in Setting menu, Applications management (my mobile phone is in spanish, so I don't know how it is called in english) I can see the list of my apps, but instead of the icon there is an standard image. Even Play Store and Google Services apps have disappeared!!

All the applications where installed in the internal memory.

My smartphone is a Samsung Galaxy S2, android 4.1.2 version.

Please, I need your help!

(Sorry for my bad english)
are you sure you had your apps in internal memory not memory card?

go to setting -> storage option and check if there is any space allocated for apps.
if no space then your phone must have been formatted