I know exactly what you are talking about! Having used my 3GS as recently as today, and most days in fact. But yes, the back does get extremely slippery, especially when sweaty somewhat oily. Throw some water on there and it’s back to normal for a bit.
I still put my SIM card in it from time to time and use it as a daily just for fun, or to disconnect a bit. Still does most of what I’d need it to do. That and the battery still holds nearly 100% of its original capacity.
I’ve never used a white one however. So I have no comparison. But I can agree and say that’s they do get quite slick!
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