Key Takeaways
- An Android gateway does not grant consent. It sends whatever you queue through a SIM clients already know.
- Appointment reminders, win-back promos, and login OTP are different legal and operational lanes.
- STOP, HELP, and a way to talk to a human belong on marketing-like traffic. Write the reminder exception with counsel.
- Quiet hours are a timezone problem. UTC “24h before” is how you text someone at 3 a.m.
- You still buy operator airtime. Platform pricing is devices plus send volume — not a compliance product.
This page is the legal-ops twin of the appointment businesses in-depth guide. Primary intent stays android sms gateway for appointment businesses — specifically what you must not pretend the Android app did for you.
Features: auto-reply and STOP, scheduled SMS. You bring the phone and operator credit. Pricing is devices plus send volume.
Inbound on the shop SIM: STOP. If the next reminder CSV still contains that row, you failed — not the modem.
STOPTransport vs permission
The gateway will send a perfectly formatted “see you tomorrow” to a number that never booked you. That is a you problem. Keep acquisition source on the contact: booking widget, walk-in card, phone call. CTIA-style messaging practices are the industry floor, not your counsel.
“They gave us their mobile for the appointment” is a reminder basis, not a lifetime licence to sell packages at 8 p.m. on Saturday.
Reminder vs promo vs OTP
Split lists and, when volume grows, SIMs. Win-back offers need STOP. App login codes need a quiet pool. OTP does not belong on the promo radio. Mixing lanes is how a haircut coupon trains filters to bury the 24h reminder.
Compliance checklist table
| Control | Reminder lane | Promo lane |
|---|---|---|
| Consent record | Booking + mobile captured for that visit | Separate opt-in; do not infer from a haircut |
| Identity in SMS | Shop name, time, how to change | Shop name, offer, STOP instruction |
| STOP / HELP | Policy with counsel; still log inbound | Mandatory honor on every send path |
| Quiet hours | Local timezone of the client | Stricter; no dawn “flash sale” |
| Frequency | Cadence you published (e.g. 24h + 2h) | Cap; stacked blasts look like spam |
| Minors | Parent/guardian number policy | Usually do not |
STOP that actually subtracts
Auto-reply can ack. Your CSV, list, and API must skip the number next time. Auto-reply overview and contact lists. One leak undoes the feature. Webhook signatures: Developer Center.
Quiet hours and timezones
Schedule in the client’s zone, not the till’s PC clock. Scheduled SMS. A 24h reminder for a 9 a.m. slot should not land at 9 a.m. yesterday in another country.
What to keep next to the MSISDN
- How you got the number and when.
- Template version sent (so you can answer “what did we say?”).
- STOP timestamp and which program it applied to.
- Not a paste of clinical or financial detail in the SMS log if you can avoid it.
Retention is your policy plus product limits. The radio already copied the body to an operator. Least data in the text is the cheap control.
Next steps
Write the two-lane policy on one page, canary STOP, prove the next send skips. Install the app. Use 300 lifetime SMS on staff numbers before a live book. This is not legal advice; it is the list we see shops skip.
Related product pages
Jump to the live product docs for this topic—not another long-form article.
- SMS API documentationLive endpoint reference
- device and SMS volume pricingPlans and allowances
- Security and Trust CenterCompliance and posture
- Android SMS gateway product guideDefinition, product, and how to buy
