There is a proven link here:
Sorry for the edit if it was good but sometimes these things are not known. An untested apk file can introduce some nasty things to one's phone.
If you apply a rom or theme - backup first!
If you don't know how to backup...Stop until you do.
hint: I name my backups like this: sg6.0_20100428 or ss4.2_20100626 to easily find them later. rom and date.
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