Key Takeaways
- Scenario 816 is tattoo-studio session deposit OTP — not salon, calendar deposits, waitlists, studio door-codes, telehealth, vet, garage, driving, notary, implant, visa, physio, or optician collect.
- Session OTP is P0. Station-ready is P1. Aftercare merch waits.
- Priced by devices and SMS send volume. You use your own phone and operator SMS credit. Free is 300 SMS lifetime, 1 device. Developer is 25,000 SMS per year.
- Starter is 2 devices; the studio spare still counts.
- A cancelled session at 10:50 must kill the 11:10 OTP still queued.
- Pin OTP deviceIds. Newsletter never shares the session radio.
Summary
Scenario 816 is the tattoo counter. Session OTP first, station-ready second, aftercare merch held until the last chair sits. Service pricing is based on device count and total SMS sent through the gateway. You need a working Android phone with a SIM and SMS credit from your mobile operator. Operator message costs are yours—we do not sell carrier SMS balance.
If the flash CSV left at 11:00 and the client is still at the door, you did not start a session. You advertised.
Not a CodeCanyon “studio SMS” pack. Device meters apply — Twilio vs Android SMS gateway.
Key takeaways
- Scenario 816 is tattoo-studio session deposit OTP — not salon, calendar deposits, waitlists, studio door-codes, telehealth, vet, garage, driving, notary, implant, visa, physio, or optician collect.
- Session OTP is P0. Station-ready is P1. Aftercare merch waits.
- Priced by devices and SMS send volume. You use your own phone and operator SMS credit. Free is 300 SMS lifetime, 1 device. Developer is 25,000 SMS per year.
- Starter is 2 devices; the studio spare still counts.
- A cancelled session at 10:50 must kill the 11:10 OTP still queued.
- Pin OTP deviceIds. Newsletter never shares the session radio.
Related reading
OTP and 2FA SMS, appointment reminders, how an Android SMS gateway works, GOV.UK Health and Safety Executive.
Context
Deposits confirm mid-morning. Clients reply from the pavement. Saturday still wants a flash CSV.
Free (300 SMS lifetime) is a rehearsal studio. Developer is 25,000 SMS per year.
Core scenario guidance
Session OTP is P0. Cancelled slots kill queued codes. Timezone is the studio city.
Session OTP roles
| Role | When | Typical fail |
|---|---|---|
| Session OTP (P0) | Client at the door / deposit confirm | Queued behind flash-day promo |
| Station-ready (P1) | Artist seated | Sent after the slot was cancelled |
| Aftercare merch | Held until last session seated | Released at 11:00 into OTP |
| Portal login OTP | Own pool, always | Dumped onto the session SIM |
Cost and ownership
Priced by devices and SMS send volume. You use your own phone and operator SMS credit. The studio spare is a billed device. Codes burn airtime.
Name a Saturday 10:00–18:00 on-call, not only weekday reception.
Operations
10:40 canary both radios. Abort: hold merch, keep portal OTP, skip queued session if cancelled. Do not “resend all chairs.”
Security and compliance
Short codes only. No consent photos plus full name in one SMS. Authenticate booking hooks. Merch is promotional.
Decision guide
Ship when 10:40 canary is green and cancelled slots kill OTP. Delay if phones lock Friday night. If handsets are forbidden, CPaaS for session OTP.
Checklist
- Primary + studio spare paired.
- 10:40 canary.
- Cancel kills queued OTP.
- Session isolated from merch.
- Portal OTP own pool.
- Airtime before Saturday.
- Battery exemptions both OEMs.
- Studio-city locale.
- Session on-call named.
- Device cap includes spare.
Next steps
Review device and SMS volume pricing, device setup, SMS API documentation.
Deep dive: production hardening
Saturday cleaner pulling USB at 10:10 is an outage at 11:00. Watch DLR, not booking 200s.
Deep dive: scaling and failure modes
Flash weekends add devices before inventing a hidden unlimited-handset SKU. Raise OEM ceilings; fair-use remains.
Deep dive: integration discipline
Idempotency on booking_id + kind (session|ready). MCP is a REST wrapper — live fields in Developer Center.
Priced by devices and SMS send volume. You use your own phone and operator SMS credit.
10:40 session drill
Canary both radios. Cancel a dummy slot; confirm OTP dies. Hold merch during the wave.
Related product pages
Jump to the live product docs for this topic—not another long-form article.
- OTP and 2FA SMS on AndroidAuthentication flows
- multi-device and dual SIM routingCapacity and failover
- SMS delivery reports (DLR)Delivery status tracking
- SMS API documentationLive endpoint reference
