Key Takeaways
- Field-service SMS is ETA, access instructions, and “job complete” — not a second copy of the work order PDF.
- Two-way on your SIM lets the customer reply “gate code 12” without installing an app. The desk phone must stay online.
- MMS for before/after photos uses the handset data path; carriers and devices must actually support it.
- Do not blast every tech’s personal number from the OTP login SIM.
- You bring Android devices and operator credit. Pricing is devices plus send volume.
Teams searching android sms gateway for field service want the customer’s lock screen to show a real local number: “we’re 20 minutes out,” then a reply with the gate code. That is a two-way SIM job, not an aggregator demo with a random sender ID.
Hub A long-tail. You bring the phone and airtime. We meter devices and send volume. Product: two-way inbox · MMS gateway.
Inbound
“Gate on the alley. Code 4411.”
Same SIM that sent the ETA. Webhook to the job, not a group chat.
What field service SMS is for
Window reminder, en-route, arrived, complete, “we need access.” The FSM remains the system of record. SMS is the last-meter channel when data apps fail in a basement.
If the only number the customer can reply to is a short code they do not recognize, you will get voicemail instead of a gate code.
Event → template → channel
| Event | SMS body includes | Channel |
|---|---|---|
| Booked | Window, how to reschedule | SMS, appointment SIM |
| En route | ETA, tech first name optional | SMS, same thread |
| Need access | Question only — no full address dump to a wrong number | Two-way SMS |
| Complete | Job id, how to see photos | SMS or MMS if the photo must live in-thread |
| Tech login to FSM | OTP | Isolated OTP device |
Dispatch on the same MSISDN
Inbound message.received must attach to the open job by from-number. Deduplicate STOP vs “stop at the side door.” Device must not Doze through the afternoon. Webhook guide · Doze.
MMS proof of work
type=mms plus an attachment URL the handset can fetch. Confirm the desk phone’s operator plan includes MMS. Many “data SIMs” do not. Fail closed to SMS + portal link. MMS attachments best practices.
Techs in basements and rural coverage
The gateway radio is at the office (or a site with signal). The tech’s connectivity is a different problem. Do not require the tech phone to be the modem unless you staff that like a desk device.
Addresses and photos
Wrong-number ETAs leak addresses. Confirm E.164. Number formats. Photos in MMS land on the customer thread and the gateway handset — retention policy applies. Data retention.
Devices and airtime
Office modem + OTP phone is two devices. Peak is late-afternoon “on my way” bursts. Free: 300 SMS lifetime. Developer: 25,000/year. Starter / Pro / Business: platform volume uncapped, devices 2 / 5 / 15. You fund operator SMS. Pause on Free/Developer at allowance.
Checklist
- ETA and OTP on different SIMs.
- Inbound replies attach to job ids.
- MMS proven on that operator, or SMS fallback.
- Staff canary: send ETA, reply as customer, see it on the job.
Next steps
Pair the dispatch phone, wire one FSM event, ignore the rest until that loop is boring. Setup · downloads.
Related product pages
Jump to the live product docs for this topic—not another long-form article.
- device and SMS volume pricingPlans and allowances
- Android SMS gateway product guideDefinition, product, and how to buy
- SMS API documentationLive endpoint reference
- download the Android gateway appGet the APK
