I don't see much difference in http://gadgets.ndtv.com/samsung-galaxy-j3-6-3112-vs-samsung-galaxy-on5-3052-vs-samsung-z3-3033.
But if having FM radio or an ambient light sensor is one of your criteria for best, it's clear. And if 9 gram of weight difference is a deciding factor, it's clear also. Anyway, my suggestion is you do your homework and read all reviews you can find.
Which is the best j3 or on5

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