Run several Android phones and SIMs as one gateway
When one SIM is not enough: how to lay out a small phone fleet, give every SIM a quota, rotate sending across devices, and rehearse what happens when one phone goes offline. Where we could not verify a behaviour, the page says so.
When one SIM stops being enough
Three honest reasons to run more than one phone. First, volume: one SIM sends serially, so a fleet multiplies throughput in proportion to its size — nothing more, nothing less. Second, separation: different campaigns or number ranges can ride different SIMs, which keeps carrier filtering per number instead of per campaign. Third, redundancy: a blocked or offline phone stops its own queue, not the whole operation.
One layout rule we hold to: one phone per SIM. Whether the gateway app can drive both slots of a dual-SIM phone is not verified by us, so we do not recommend building on it. Test it yourself if a dual-SIM device is all you have.
Build the fleet in five steps
SIM rotation and per-SIM quotas require the Enterprise edition or above.
Give every phone a fixed address
Reserve each phone's IP in the router's DHCP table before adding it. Expected: each phone keeps its address across reboots, so the PC never loses it.
Add every phone as a device
Install and pair each phone exactly as in the single-phone setup. Expected: every device shows online in the device list with its own entry.
Label devices by SIM
Name each device with the carrier and the number it holds. Expected: per-SIM reports read as people think about the fleet, not as raw device IDs.
Set per-SIM quotas and enable rotation
Give each SIM a daily quota below what its carrier tolerates, then turn on rotation so the queue spreads across devices. Expected: the report shows sends distributed across SIMs, and a SIM that hits its quota pauses while others continue.
Rehearse a phone going offline
During a small test campaign, switch one phone off. Expected: that device is marked offline and its queue waits; the other phones keep sending. When it returns, its queue resumes. Resend any failed batch once, from the delivery report.
Failure symptoms you will actually meet
| Symptom | Likely cause | What to do |
|---|---|---|
| One SIM fails every message while others send | Carrier has blocked or capped that number | Pause the SIM, send a manual test from the phone itself, then contact the carrier; do not rotate more traffic onto it |
| Load is uneven across phones | Quotas set too tight on some SIMs, or one phone keeps dropping offline | Check the per-SIM report, then the offline history; fix the flaky phone's power and IP before rebalancing quotas |
| All phones offline at once | Network or power event, not the app | Check the router and the power strip first; the phones cannot reach the PC either |
| Duplicate messages after a retry | A batch was requeued without checking what actually failed | Requeue from the delivery report's failed rows only, and only once |
What we deliberately do not claim
- No invented carrier caps. Daily limits differ per carrier and plan and are rarely published; the safe quota for your SIMs is something you establish with a small test campaign, not a number we can print here. See rate limits.
- No automatic re-routing on carrier block. Whether the software re-routes a blocked SIM's queue to another phone mid-campaign is not verified by us; treat re-sending failed batches as a manual step from the report.
- No dual-SIM guarantee. One verified sending SIM per phone; dual-SIM behaviour is untested by us.
This guide is part of the Android gateway cluster: overview, multi-SIM, rate limits, troubleshooting.
Questions about multi-SIM fleets
How many phones can one PC drive?
We do not publish a verified ceiling. Practically, fleets are limited by Wi-Fi reliability, power and the attention you give each device; start with two or three phones and scale after a week of stable reports.
Does rotation split one campaign across SIMs?
Yes. With rotation enabled, the queue spreads a campaign's messages across the devices, and per-SIM quotas stop any single number from tripping its carrier's limit.
Can I route specific number ranges to a specific SIM?
Routing by number range is listed as a capability of the multi-device editions. Confirm the exact matching rules against your edition in the trial before designing around them.
What happens to the queue when a phone goes offline?
That device's queue pauses and its messages wait; other devices continue. When the phone comes back, its queue resumes. Failed batches are re-sent manually from the delivery report.
Is a dual-SIM phone enough instead of two phones?
We have not verified dual-SIM sending, so the supported layout is one SIM per phone. If you test a dual-SIM device successfully, treat the result as your own finding, not a guarantee.