Flash calls: Third-party aggregators save cash even as telcos red-flag new verification method

​When an app requires verification, the process starts with a third party initiating a call that lasts a few seconds. At the same time, a code using digits from the caller’s number is generated. The app seeking authentication then uses an application programming interface to read the last call from the recipient’s log and automatically picks up the code that was created, thus facilitating the verification.
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