User Authentication: Weighing Up the Best Identity Verification Channels for Your Website or Mobile App

“87% of customers agree that companies should be putting more effort into delivering a consistent experience.” (Source)

“IoT devices experience an average of 5,200 attacks per month.” (Symantec)

“The financial services industry takes in the highest cost from cybercrime at an average of $18.3 million per company surveyed.” (Accenture)

“More than 93% of healthcare organizations experienced a data breach in the past three years.” (Herjavec Group)

SMS Identity Verification

Termii’s API documentation page
  • It is the most familiar among mobile users. SMS is straightforward to know, straightforward to use, and applicable for many mobile users in any part of the globe.
  • It’s universally accessible on mobile devices. Practically, all mobile devices are SMS-enabled; a great number of tablets, laptops, and even desktops send and receive SMS messages as well.
  • It has a remarkably high success rate. SMS identity verification is straightforward to understand with high success rates, providing a stronger overall experience for users.
  • SMS messages could also be delayed. High-traffic periods and remote locations will delay SMS messages, and thus SMS-based codes.
  • Temporary codes can be intercepted. Though rare, bad actors may use social engineering to intercept temporary codes from users and so reconfigure their credentials for unauthorized access to accounts.
  • It may be more pricey than other channels. SMS is often a more expensive identity verification method than Voice Verification Methods. Providing viable alternatives will thus boost cost savings.

Voice Verification

  • It is ideal for users with special needs. SMS is also difficult for a few users. Hearing a code aloud can be a much better choice.
  • It can use a fixed phone line for verification. Users can set up landline phones for Voice Verification if they do not have access to a mobile phone.
  • It is an ideal backup verification method for SMS. For users who prefer SMS, Voice Verification is a great backup if they don’t have access to mobile or other compatible devices.
  • It is a perfect backup/alternative verification channel for SMS. For users preferring SMS, Voice Verification could be a nice backup if they do not have access to mobile or alternative compatible devices.
  • It will be less recognized by most users. Given that this method isn't used as commonly as SMS verification methods, it could be confusing to some first-time users.
  • It needs sharp retention. Users must recall the OTP code, or they risk needing the message repeated or may be forced to try again.

Email Verification

  • Familiar data requirement — users are used to providing their email to a service for important account updates and password reset emails.
  • Easy onboarding — just like SMS verification, email verification does not require another app or any additional setup to configure.
  • Using email means that your users don’t have to give you additional personally identifiable information (PII) like a phone number.

WhatsApp Verification

  • As a software channel, WhatsApp won’t charge for undelivered messages and isn’t exposed to fraud that exploits the telecom network.
  • Unlike the WhatsApp Business API, which you may use for customer support, Verify WhatsApp lets you start sending unthrottled OTPs right away.



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Termii Inc.

Termii Inc.

Termii helps businesses verify their customers across SMS, voice, and instant messaging channels.