How it plugs in
—Public API
NoOpen source
YesFree tier
Signal on Chat APIs6.1#19 of 32
Emitter is a real-time publish-subscribe messaging service for connecting online devices.

Pricing
- Startfree forever · 1 GB data transfer · 50 unique devices · storage coming soonFree
- Scale$10 per month · 15 GB data transfer · $1.00 per extra GB · 500 unique devices · $0.10 per extra 100 · storage coming soon$10/mo
As emitter.io lists them, checked 9 Oct 2026.