How a Manfrotto-style magic arm clone works.

The Manfrotto magic arm is a very common item used in the film and television industries for quickly clamping cameras, lights and small monitors to any grippable surface and setting a position.
This one is a cheap mass produced clone, which has the disadvantage of being flimsier than the real thing, but the major advantage of being about a tenth the price.

For lightweight video making it's a very useful gadget.

Here's an eBay search link to find one. Make sure you get one that includes the clamp.
https://www.ebay.com/sch/i.html?_from=R40&_nkw=magic+arm+clamp+11&_sacat=0&LH_TitleDesc=0&_sop=15&rt=nc&LH_BIN=1
Target price $12 to $15.

The phone holder is usually a separate item sold as a phone tripod mount.

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