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How it works

Prelude partners with many to guarantee the highest possible delivery rate at the lowest possible cost. We also use multiple to reach your users thanks to our routing engine which compares all available routes and selects the best one for each individual user.
For example, if your user is in an area with poor cellular network coverage and has an Android phone, Prelude could give priority to RCS or WhatsApp rather than SMS to deliver the OTP as these channels are known to be more likely able to reach the user
Prelude is constantly keeping and updating statistics on the conversion rate for each provider/channel pair. To measure these rates, we send a unique OTP for each attempt (retry). This helps us pinpoint exactly which provider/channel pair successfully converted the user.
This is why, when you’re using the custom_code feature (meaning OTP generation happens on your side), you must send a unique custom code for each attempt.

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Why we built it

We built this system after years of experience working at Zenly, a social network acquired by Snap Inc. in 2017. Having to deal with a large number of users in many countries, we quickly realized that the traditional approach of using a single provider was not enough to guarantee both the best conversion rate and the best cost. We also realized that every big player builds their own routing engine and that there was no real good solution available on the market.

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Strategic Trade-offs

You can configure the routing engine to better fit your needs using Strategic Trade-offs. Strategic Trade-offs are a set of 3 options that you can use to configure the routing engine per country: cost, balanced, and conversion.
  • cost will prioritize less expensive at the expense of conversion rate.
  • balanced will try to find the best compromise between cost and conversion rate.
  • conversion will give priority to the with the highest conversion rate, even if it means paying a bit more.
We recommend using the default balanced option for most use cases and selecting conversion for countries that are important to you. The cost option can be used for cost reduction.
To configure a country’s strategic trade-off, click on the Strategy button in the Dashboard.