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Authentication
by incoming call

We offer a convenient alternative to traditional SMS messages for phone number verification during registration, authentication, or verification of important user actions on your project, website, or application.
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Commercial Offer

About the Service

Our service allows you to completely replace expensive SMS messages with a cost-effective user authentication method via incoming call using the last four digits of the phone number. The service can be used as a standalone solution or in combination with your existing SMS gateway.
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How We Compare to SMS Services

Allo Service
Authentication cost starting from $0.006 per call
Instant authentication with no delays
100% guarantee of code delivery to the user
Landline number authentication supported
Single price for all carriers
SMS Services
High costs for SMS operator services
Long wait times or lost SMS messages
SMS delivery failures
Mobile numbers only
Prices vary by carrier

Key Advantages

Every day we strive to make our service better and more convenient!
Simple and Convenient API
We offer several types of easy integration options to minimize the code on your side
Committed to Successful Authentication
In case of issues, we make free retry attempts until we confirm a successful connection.
Flexible Volume-Based Pricing
Unified rates proportional to your volume — from $0.006 per request for all client carriers.
Reliable Infrastructure
Flawless performance and service quality are ensured by a reliable international-scale ITSP company.
Start saving on
SMS authentication today!
We designed the service for simple and fast integration into your project.
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