In the Places and Devices modules, you can select multiple rows using the multi-select tool, and the Actions menu will appear. From there, you can Delete you checked off rows, choose to Export their data to a csv, or deploy a Bulk Edit to the selected rows. With the Bulk Edit tool, you can change any settings (either one individual setting like Climate Mode, or all available settings) and those changes will affect all of your checked off rows.
You can also push a defined Preset to all your checked off rows. By combining the power of Presets with the Bulk Edit feature, you can literally change every setting on every device in every unit on your property with just a few clicks!