Android SMS Gateway Scenario 970: NGOs USSD requests in practice

Android SMS gateway scenario 970 is an NGO country office that already owns Android handsets and prepaid SIMs. They need USSD for balance and simple menus (*123# style), plus SMS for field alerts. The failure is treating USSD like a guaranteed API and treating donor SMS like operations.

Priced by devices and SMS send volume. You use your own phone and operator SMS credit. USSD gateway. Live parameters: Developer Center. Operator menu behaviour varies by market — see GSMA for industry context, not a country playbook.

USSD is a carrier menu, not SMS

USSD sessions are short, region-sensitive, and can die mid-tree. You are automating a phone keypad, not a REST resource the operator promised you. Log session ids, last menu step, and timeout. Do not parse screenshots in Slack as the system of record.

If the field blast goes out on a SIM whose last USSD balance check failed, you paid for silence and you burned staff trust.

Ops alerts vs fundraising

Caps: Starter 2 devices, Professional 5, Business 15. Multi-country offices usually hit the device meter before the platform volume meter.

Airtime checks before a blast

Prepaid death is the outage. Schedule USSD balance before any bulk ops SMS. If the menu changed after a carrier promo, the parser fails — treat that as a change ticket, not a silent zero.

Failed SMS retries still cost airtime. Budget them. Operator cost how-to.

Timeouts are expected

Backoff. Cap retries. Do not hammer *123# from a worker every 10 seconds. Some networks throttle USSD harder than SMS. Document which codes work per MNO in the country office runbook.

Field SIMs and dual-slot maps

Dual SIM fails when slot maps drift after reboot. Dual SIM. Re-pair after SIM swaps. Spare charged devices in the capital office matter more than a promised SLA.

REST only — PHP samples, C# samples. MCP wraps REST.

Beneficiaries are not a list

Programme participants are not a fundraising CSV. Store purpose with the number. Opt-out on outreach is not optional because the message “feels operational.” Blacklist · STOP.

Devices, volume, prepaid

Priced by devices and SMS send volume. You use your own phone and operator SMS credit. Free: 300 SMS lifetime. Developer: 25,000 SMS per year. Starter / Pro / Business uncap platform SMS volume; devices still meter. We do not sell carrier packs and we do not cash out unused SMS as prepaid credits.

Pricing.

Country office ownership

Name who tops up, who owns pairing, who updates USSD codes after a carrier change. HQ should not fire a cross-border blast from a laptop timezone. Canary staff numbers in-country first.

Menu data and staff phones

USSD responses can include balances and identifiers. Restrict who can trigger sessions. Do not screenshot menus into public Slack. Rotate API keys when a local contractor leaves. Not a turnkey “sell SMS” white-label.

When USSD is the wrong tool

If the MNO has no stable code, or you need a signed API, use the operator’s business portal or a local aggregator for that menu. Keep SMS alerts on Android when local numbers and airtime economics win.

Checklist

• Ops SMS and fundraising SIMs are split.
• USSD codes documented per MNO with timeout policy.
• Balance check before bulk ops SMS.
• Slot map re-verified after reboot.
• Spare charged device in-country.
• Consent purpose stored with numbers.
• On-call and top-up owners named.

Next steps

Run one USSD balance on the field modem, then one staff SMS, then a deliberate timeout drill. Setup · API docs.