Apollo MSR-2

Quick verdict

The Apollo MSR-2 packs an absurd number of sensors into one little board - presence, temperature, pressure, lux, and more. It's an ESPHome tinkerer's dream for room-aware automations. Don't expect a polished consumer experience though; this is built for the HA crowd.

Standout: Dense multi-sensor package for Home Assistant users who want more than simple motion triggers.

Notes last checked Oct 26, 2026.

Compatibility snapshot

Why it stands out

• integrates natively with Home Assistant via ESPHome with zero cloud dependency
• rich sensor set beyond simple presence - includes temperature, pressure, light, and mmWave
• all data stays on your local network with no vendor account required

Reasons to hesitate

• still more enthusiast-oriented than mainstream smart-home sensors
• mmWave sensitivity requires careful mounting height and angle tuning to avoid false triggers
• not a good pick if you do not want Home Assistant-style tinkering

Best for

• advanced Home Assistant users who want richer room telemetry
• buyers who want local presence plus extra environmental sensing

Avoid if

• you want the simplest possible occupancy sensor
• you mostly care about Apple Home, Google Home, or Alexa app polish

Privacy and local-control notes

A strong privacy and local-control option because core value comes from local ESPHome integration, not account-tied cloud services.

Home Assistant support: supported · integration path: ESPHome / native Home Assistant.

Built with ESPHome - see the ESPHome guide for Home Assistant →

Buying reality check

Price notes: Apollo Automation sells the MSR-2 direct at $37.99 (vendor store, in stock, verified 2026-09-02). Quote that figure as the price. The Amazon listing read $20.99 on 2026-08-30 and had NO buy box at all on 2026-09-02, so preferDirect is set and the maker's store is the primary buy surface. Good value for buyers who will actually use the extra sensing data; overkill if you only want basic room occupancy. On October 26, 2026 the Amazon listing was still out of stock, while Apollo's store had the base MSR-2 in stock at $37.99 and the version with CO2 at $57.99.

One verified price read so far: $20.99 at amazon on Aug 30, 2026.

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