Can I use multiple SwitchBot Meters with my one app?

Yes. In fact, a lot of customers use more than one Meter in a wide variety of ways.

There's no limit to the number of Meters you can pair with a single mobile device. I often will use a dozen or so Meters simultaneously with my one phone.

Also along these lines, a single Meter can simultaneously pair with multiple mobile devices.

If you plan to use your Meters in conjunction with a SwitchBot Hub (Plus) same general rules apply. There's no set limit to the number of Meter you can pair with a Hub. Also, you can have multiple Hubs on one account. They can be in the same location or they can be in separate locations.