Can unused list credits roll over as prepaid SMS we sold?

No. We do not sell carrier packs. Unused platform allowance is not cash-out airtime. You buy SMS from the operator.

Do seller and buyer lists count separately toward Free contacts?

Free allows 300 contacts total on 1 device. Segment in software; the meter is still one list ceiling.

Is this a Laravel SMS SDK product?

No. Use HTTPS/JSON against the gateway. Code samples are conceptual; Developer Center owns parameters.

Android SMS Gateway Scenario 35: Marketplaces contact lists in practice

Key Takeaways

Store consent source and timestamp with every marketplace MSISDN.
Seller blast lists never share the buyer-login OTP device.
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. Service pricing is based on device count and total SMS sent through the gateway.
Free: 1 device, 300 SMS lifetime, 300 contacts — not a multi-vendor CRM.
STOP must apply per list owner, not “the marketplace” as a blob.
Live list APIs live in Developer Center, not this scenario.

marketplace · lists

buyer OTP ≠ seller promo ≠ ops alerts

A scraped seller CSV is not a contact list. Without consent rows, every send is a compliance and airtime leak.

Vertical playbook: multi-vendor lists

Marketplaces mix three populations: buyers proving login, sellers getting payout or policy SMS, and marketing for featured listings. Only the first is authentication. Tag each number with tenant_id and purpose. When a seller is suspended, suppress their promo segment without touching buyer OTP.

Import hygiene: drop landlines, drop shared office numbers used as OTP sinks, and pace the first campaign. Platform send volume on paid tiers is not a license to ignore STOP or quiet hours.

Budget devices for peak festival traffic. Fifteen Business devices still need fifteen charged Androids and fifteen operator balances. White-label branding, if contracted, does not change that meter.

Failure map

Symptom	Likely cause	First move
Buyer OTP delayed during promo	Shared device	Split pools; pause featured-listing blast
STOP ignored for one seller	Global suppress missing tenant	Per-tenant opt-out table
Import hits contact cap	Free 300-contact ceiling	Upgrade; do not silently drop rows
Chargeback language on “unused SMS”	Wrong mental model	Refund platform fees only; never airtime

Summary

Marketplace contact lists fail on consent metadata, not on Laravel syntax. 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. Service pricing is based on device count and total SMS sent through the gateway. Seller and buyer segments must not share the OTP pool. Free caps lists at 300 contacts on 1 device.

Key takeaways

See key takeaways — vertical-specific owners, meters, and isolation.
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.
Service pricing is based on device count and total SMS sent through the gateway.
Free: 1 device, 300 SMS, 300 contacts.
Developer Center owns live API parameters.
Canary on staff numbers before production traffic.

Context

Teams use laravel sms gateway scenario 35 to translate a vertical workflow onto an Android SIM gateway.

Radio reality still wins: offline phones and OEM killers break scenarios overnight.

Cross-link hub cornerstones instead of rewriting the product overview.

Keep examples conceptual until Developer Center confirms live request shapes.

Budget airtime for retries — failed loops still cost operator credit.

Core scenario guidance

For laravel sms gateway scenario 35, map each customer moment to a device pool and fallback path.

Separate configuration mistakes from radio failures during incidents.

Write acceptance criteria before seasonal or clinic-hour traffic.

Prefer gradual rollout with feature flags when automation is involved.

Cost and ownership

Model cost as devices + volume + operator airtime.

Failed retries still burn credit during scenario experiments.

Assign who owns SIM top-ups and spare handsets.

Keep marketing spend out of OTP device pools.

Operations

Daily checks: pairing health, battery, queue depth, and DLR anomalies.

After OEM updates or SIM swaps, re-test the scenario path end to end.

Keep a spare charged device ready for failover drills.

Name an on-call owner before unattended sends go live.

Security and compliance

Protect API keys per environment; rotate after contractor access ends.

STOP and consent still apply on promotional scenario lanes.

Avoid logging full OTP bodies into shared chat.

Verify webhook signatures and TLS on every callback path.

Decision guide

Ship laravel sms gateway scenario 35 when owners, metrics, and fallbacks are written.

Delay if you cannot explain offline-phone behavior during peak hours.

If zero phone ops is mandatory, evaluate CPaaS for that lane.

If local SIM economics matter, harden the Android path and monitor airtime.

Checklist

Scenario moments listed with owners.
OTP vs marketing isolation confirmed.
Spare device funded and paired.
Canary on staff numbers passed.
Developer Center checked if API-shaped.
Webhook/DLR monitoring ready.
Airtime budget includes retries.
On-call owner named.
Rollback path documented.
Hub cornerstone reviewed.

Next steps

Return to Laravel SMS gateway guide, compare device and SMS volume pricing, open device setup guide, and confirm APIs in SMS API documentation.

Deep dive: production hardening

Webhook signature verification is non-negotiable for scenario automation.

Document who owns SIM top-ups for multi-site scenario rollouts.

Prefer honest latency expectations over marketing claims about global SLAs on SIM paths.

Scenario playbooks still bill by devices and SMS send volume. You bring the Android phone and operator SMS credit.

Developer Center owns live API parameters. Scenario blogs teach process and failure modes, not endpoint catalogs.

Ecommerce webhooks must verify signatures before they trigger SMS sends.

Clinic reminders need consent records and STOP handling even when messages feel transactional.

Logistics ETAs should degrade gracefully when devices go offline mid-route.

Edtech OTP spikes at exam windows — capacity plan devices before the semester starts.

Fintech OTP is high-stakes: isolate devices, rotate keys, and avoid logging full codes.

Real-estate nurture is promotional; keep it off OTP SIMs and honor quiet hours.

Restaurant reservation SMS still needs STOP on marketing lanes.

SaaS onboarding OTPs should canary on staff numbers before paid scale.

Field-service dispatch needs two-way inbox ownership so techs are not double-booked.

Marketplace seller alerts need multi-device failover when a single phone is the SPOF.

NGO outreach must separate fundraising blasts from operational alerts.

Appointment businesses live on reminder deliverability the morning of the visit.

Bulk CSV import needs validation before radio send; bad rows burn airtime.

Scheduled SMS must survive device sleep and timezone mistakes.

Auto-reply and STOP protect promotional lanes — never auto-reply into OTP threads.

Dual SIM routing fails when slot maps drift after reboot without re-pair.

Multi-device failover only helps if spare phones stay charged and paired.

MMS attachments inherit carrier size and APN limits.

USSD requests are carrier- and region-sensitive; treat timeouts as expected.

Contact lists need consent metadata stored with the number.

OTP priority queues fail when marketing blasts share the same device pool.

Spare charged devices matter more than brochure SLAs when phones send the SMS.

Airtime surprise bills happen when bulk loops ignore radio pace.

OTP and marketing must stay on separate lanes on every scenario.

Never claim unlimited free cloud SMS credits with no device or volume meter.

Name an on-call owner before unattended schedules go live.

Canary on staff numbers before customer OTP.

Battery exemptions and OEM killers dominate overnight reliability.

Cross-link Setup, Pricing, Downloads, and Developer Center with keyword-rich anchors.

If zero phone ops is mandatory, evaluate CPaaS for that lane instead.