Which is a better estimate for weight of a smartphone?
180 grams
If the object is small and light weight, grams will give an accurate weight measurement, and if the object is larger or heavier, you may want to use kilograms. That's because the kilogram is much larger - there are 1,000 grams in 1 kilogram. milli grams are used to measure very light objects. there are 1000 mg in 1 g.