Guys - do you know what a JPEG is? It is a compressed format of image. Every time you edit it, it get unpacked, data is change and it is repacked. There is of course loss of information in the process.
And those who want 612x612 look the same as 13MP image, please start reading about resolution and detail as there is NO PHONE or DSLR or ANY OTHER CAMERA in this universe that will prevent JPEGS from degrading when changing resolution.
You are simply noticing it now, because S4s camera at 13MPx delivers enough details to notice the degradation.
OT MaxDB, CD1, CD5, J5, GD96, ME45, T68i, X6, CX65, A925, E398, MPx200, X6-2, OT715, D600E, W810, M600i, BB8100, W880, N95-2, P1i, Ignito, W880, X1, MS1, MS2, TP851, XT910, GTab 10.1, SGS3, Galaxy S4, Galaxy Note 10.1