Good idea but useless.
You can SMS that long code to a paid number to validate the batch of tablets.

Good idea to have an option to validate.
1. But practically who will type such long code?

2. Paid SMS?

3. What about the privacy? Mobile numbers are tightly tied to people.
That image code has the same number.
It could have been a QR code directly pulling the info from web or at least a site where one can validate. Its easier and cheaper to type on a pc than phone no?

Difference between idea and implementation.

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