Flash Call sandbox is live

Verify phone numbers with a missed call. Test it before you ship.

The BTS developer playground gives you sandbox keys, a phone that rings in your browser and the production API contract — so the code you write here goes live by changing one URL.

Request access Log in

terminal

curl https://api.btsplayground.dev/api/v2/flash_calls/fc_anumber \
  -H "Authorization: Bearer sk_sandbox_…" \
  -H "Content-Type: application/json" \
  -d '{"b_number": "+999 000 1234"}'

{ "request_id": "3f6c…", "a_number": "34911418273" }

Sandbox keys in a minute

Create sk_sandbox_ keys scoped per product. Same requests as production, no charges.

A phone in your browser

Your virtual number rings in the web mock phone. See the caller ID and the code the SDK would read.

Webhooks you can watch

Signed events and production-format CDR callbacks, with a built-in inbox and replay.

Docs that match the API

Reference generated from the same OpenAPI spec the sandbox serves, plus the Android guide.