FAQ

Does it need a modem?

No. No cellular modem is needed on site. Arifa sends SMS through Africa's Talking, over the gateway's internet connection. See the overview.

Does the gateway need an open port?

No. Arifa opens no port and accepts no inbound connection. The gateway only needs outbound HTTPS on port 443 to Africa's Talking, and Arifa fetches replies by asking for them. See the network requirements.

Can it use Twilio, or another SMS provider?

Not today. Africa's Talking is the only SMS provider Arifa works with. See Limits.

Which networks work?

Arifa hands each message to Africa's Talking, which passes it to the mobile network. In Kenya, Arifa checks that numbers are mobile numbers, written as 07..., 01... or +254....

On Airtel Kenya, check the cost of the first SMS: a line starting UNEXPECTED COST can mean it was billed as international traffic. Test every on-call phone before going live. See Going live.

What does it cost?

Arifa itself is free and open source, under the Apache License 2.0. SMS are billed by Africa's Talking to your account: see their pricing page (link checked on 16 October 2026). The sandbox costs nothing, so the quick start is free.

Each send logs its cost, the optional confirmation SMS costs one more SMS per reply, and Maximum SMS per Hour caps what a runaway alarm can spend. See Going live.

Can a user have several phones?

Yes. Give the user one SMS contact per phone. Each number gets the alarm SMS, and a reply from any of them acknowledges the alarm. See Connect to an alarm.