SMS OTP, done right
An SMS OTP is a one-time code delivered by text. It's the workhorse of online verification because nearly everyone can receive a text — no app to install. The hard parts aren't generating the code; they're getting it delivered and making it painless to enter.
Deliverability — the part nobody warns you about
Carriers filter A2P traffic aggressively, and a flagged sender means codes that silently never arrive. iBlueText sidesteps a big chunk of that by sending to iPhones over iMessage — which doesn't go through carrier SMS filters at all — and routing Android numbers over SMS.
Autofill: don't make them type
Every manual digit is a chance to bounce. iBlueText's codes support iOS one-tap autofill and Android WebOTP zero-tap by including the domain-bound code format browsers recognize. On Android the code can fill itself; on iPhone it's one tap above the keyboard.
A format that converts
Six digits, a clear sentence, and a short "expires in 5 minutes" note. Keep the message tight so the code is the first thing they see — and never bury it under marketing copy.
Related
Frequently asked questions
Why do SMS OTPs sometimes not arrive?
Usually carrier filtering or sender-reputation problems. Delivering over iMessage to iPhones avoids that filtering entirely, which is how iBlueText improves delivery.
Can the code fill in automatically?
On Android Chrome, yes — zero-tap via WebOTP. On iPhone it's a one-tap suggestion above the keyboard. iBlueText formats codes to support both.