SMS gateway vs OTP verification API: what is the difference?
An SMS gateway delivers messages. An OTP verification API also makes, checks and expires the code. Here is what each does and when you need which.
ComparisonsBest OTP verification APIs in Kenya (2026): how to choose
A fair guide to OTP verification options for Kenya in 2026: what to compare, how Africa's Talking, Twilio, Infobip, Vonage, Termii and Tambua differ.
ComparisonsTwilio Verify alternatives for Africa: what to compare before you switch
Considering a Twilio Verify alternative for African traffic? Compare pricing model, fallback, sender IDs, local channels and M-PESA before you switch.
How to OTPHow do you send an OTP SMS in Kenya?
A practical guide to sending OTP SMS in Kenya: number format, sender ID, code rules, expiry, attempt limits and what to do when the SMS does not arrive.
How to OTPHow do you reduce OTP delivery failures in Kenya?
Why OTPs fail in Kenya and how to fix it: number format, sender ID, resend design, channel fallback to WhatsApp and voice, and delivery monitoring.
Why OTPWhy does your business need multi-channel OTP verification?
One OTP channel is a single point of failure. See why multi-channel OTP with fallback improves sign-ups and security, and what to watch for.
How to OTPHow do you implement phone number verification in Kenya?
A step by step guide to phone number verification in Kenya: collect, normalise, send, verify, secure with limits, and add M-PESA or fallback channels.
Security and fraudHow do you stop SMS pumping on an OTP endpoint?
Layer rate limits, CAPTCHA, country filtering and spend caps. No single control stops SMS pumping, but together they make it unprofitable.
Why OTPWhat is an OTP and what is it used for?
An OTP is a short code valid for one use that proves a person controls a phone or inbox at a specific moment.
How to OTPHow do you generate an OTP code securely?
Use a cryptographically secure random source, not Math.random, and pad with zeros. Short examples for Node, Python and Go.
OTP in AfricaWhy does SMS OTP still work so well in Africa?
SMS needs only a basic signal and no data plan, which fits mobile-first African users and feature phones.
Security and fraudWhat is SMS pumping (AIT) and how does it hit OTP endpoints?
SMS pumping is fraud where bots trigger paid OTP messages to inflated-traffic numbers. Here is how it works and what the bill looks like.
ComparisonsSMS vs WhatsApp vs voice vs email OTP: which channel should you use?
A plain decision guide to choosing between SMS, WhatsApp, voice and email for one-time passcodes, based on your users and risk.
Why OTPOTP for betting apps: sign-up, login and withdrawals across Africa
How betting apps use SMS, WhatsApp, voice and M-PESA OTPs for sign-up, login and withdrawals in Africa, with automatic fallback when a code does not arrive.
Why OTPWhy verify a phone number at signup?
Phone verification at signup confirms the number is real and reachable, which cuts junk accounts and gives you a working contact channel.
How to OTPHow many digits should an OTP have?
Six digits is the usual choice. Learn why shorter codes weaken you and how attempt limits matter more than length.
OTP in AfricaSMS or WhatsApp for OTP when mobile data is patchy?
When data is intermittent, SMS is the safer first channel and WhatsApp works best as a second attempt.
How to OTPHow do you verify a phone number at betting sign-up?
Send a one-time code to the number, ask the player to enter it, and only then create the account or unlock the bonus.
Why OTPWhat is an OTP? A developer's guide
A developer's guide to one-time passwords: how an OTP works, the right length, expiry and attempt limits, delivery channels, and building a safe flow.