That's one of the common ways to do it, if the video does what I think it does (only watched a couple seconds)
Method 1: Cut away the plastic covering the innersd, as there isnt that much
Method 2: Completely disassemble/reassemble the device, which is a huge amount of work.
Method 2 also must be repeated every swap, method 1 doesnt, but is a permenent change.
I know the S5 will accept a 4/8gb one without much issue.
16/32gb I dont recall, they may have issues.
A 64 one would be an SDXC, can you see the entire card in SDHC compability mode?
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