Wrist based cuff works well on my weird body, upper arm auto pressure cuffs tend to cut off my circulation and make my heart wig out. As such, this actually works better for me than the ones in the hospital. The integration with the smartphone app is a wee bit rinky-dink but does what it says it does perfectly well. Two users can easily track their measurements separately and sync their data to separate phones, you just have to set a physical switch on the device to change users.