If I order multiple square readers can several people use the readers and the app with their own devices at the same time? Can the app be opened and functional on several different devices simultaneously?
Yes, actually you are able to use the same account in different devices and different readers.
How?
Download the App for your device.
Open the App and then you need to sign in by your user account etc on each Device.
You can also give each device a unique Code to sign in with.
I prefer the Device Code. As if you gave the Code to an employee you can delete the Device also from the Back office.
Go here:
https://squareup.com/dashboard/
Select Devices on the Left Column.
This will open another Screen.
Click Add a Point of Sale.
Then it will ask you different things that you can Fill out.... Like Device NickName
Location...
Type of Square settings POS or Retail or Restaurant
If this is to use shared for an employee that you can edit.
I would recommend doing this and getting a Device code for each new POS.
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