SwitchBot hygrometers are $13.30 for prime day (https://www.amazon.com/SwitchBot-The...ef_=ast_sto_dp).

I use these and have found them to be quite reliable and accurate.
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Thanks for the heads up, Michael!
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Do you need the hub in order to view the stats on your phone?
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Thanks Michael! :-)
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You do not need the hub to see the stats when you are on the same network (e.g., at home). If you want to monitor the hygrometers when you are out and about, then you do need the hub. I don’t use the hub so I can’t tell you anything else about it.
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