So far, in my opinion?
My finger.
I was always a PDA fan, and I don't like the fingerprints.
So having a stylus was one of the first things I thought of.
BUT, . . . I have tried 3 different ones now. (fortunately they were all really cheap on eBay.)
I have hated each and every one.
I just feel you have to press too hard, and concentrate to hard.
There may be one out there that could change my mind.....
But I am not going to hold my breath.
.