Quick Answer
Cascade is a Developer API for outbound delivery of OTP and short links. OnlineSIM in search scenarios more often means number rental/online-number services.
Class vs class
| Cascade | OnlineSIM class (typical) | |
|---|---|---|
| Task | Code to your user’s number | Number rental/activation |
| Cascade API | /otp/send, /otp/verify |
Different model |
| Cascade channels | WhatsApp, Telegram, SMS | More often inbound SMS |
| Cascade price | from 1 ₸ / tokens | Check with the provider |
When to take Cascade
You need OTP integration into a product: /use-cases/developers, /docs.
When to look at OnlineSIM
You need a temporary number that is not your user’s — that is not Cascade. See also vs SMS-Activate and FAQ.