Zhiyun Smooth 4 was one of the smartphone stabilizers I tested that comes closest to the ideal stabilizer. Of course I'm talking about a $ 125 stabilizer, a top of the line.
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It is worth remembering that I have not yet tested one that I can say that the ideal, all bring some undesirable feature. Anyway, the best tested so far were the Dji Osmo Mobile 2 and him.