Yes, you are probably right, one would have to calculate if the centrifugal forces outweigh the air buoyancy. Something probably more important is the humidity, as most plastics can absorb several % of their weight in water. For example, nylon can absorb over 10% of its weight in water; other plastics absorb much less, but still quite significantly, increasing the weight of the Mini 5 Pro by several grams.I called him but I got his voucemail. Google says Yes, objects weigh slightly less at higher altitudes because their distance from the Earth's center increases, which reduces the gravitational force. While the effect is measurable with precise instruments, it is not noticeable in daily life and is far outweighed by the effect of buoyancy, which also decreases with altitude due to less dense air.