Shelly 1 Mini Gen3 vs Shelly i4 Gen3

The Shelly 1 Mini Gen3 wins overall. It is cheaper, includes an actual relay with dry and wet contact modes, lists overheating protection and comes with a 3-year warranty. The Shelly i4 Gen3 is marginally better rated, but it has no relay and only reads inputs.

One controls, the other observes. The Shelly 1 Mini Gen3 has a single relay channel rated for 8A and 2000W, so it can switch a light, a pump or a garage door. The Shelly i4 Gen3 has four inputs and no relay, so it triggers automations rather than powering anything.

Yes, and that is a common setup. The Shelly i4 Gen3 sits behind a multi-gang switch plate reading four buttons, and those presses trigger scenes that switch loads through relay modules like the Shelly 1 Mini Gen3 elsewhere in the house. Both are small enough to hide in a back box.

The Shelly 1 Mini Gen3 does require a neutral at the install point, which is worth checking before you buy. The Shelly i4 Gen3 does not, since it only monitors switch inputs rather than powering a load through a relay.

Buy the Shelly 1 Mini Gen3 if you want the smallest, cheapest way to make an existing circuit smart while keeping the physical switch working. It fits behind an outlet or inside an appliance, handles dry and wet contacts, supports Matter, and gives instant local control with a 3-year warranty.

Buy the Shelly i4 Gen3 if you want to keep your existing wall switches and use them as smart triggers, or if you need to bring dry-contact sensors and buttons into Home Assistant or Alexa. Just remember it cannot switch a load, so pair it with a relay module.