The app is asking to access my Contacts to use the Ranking feature. Why is this necessary?

The app asks for your contact acess so that you can share results with others.

How many people can share this scale? Will the data upload only the current measurements to the app running whoever's phone is connected?

Multiple users can separately and independently sync to the scale through their own InBody App. In other words, only one user can log into one application. And only one app can be connected to one device at a time. In order to switch user within application, previous user must log off of their application and re-login with different account. In order to switch user on a device, establish a new connection with new user's account, application, and phone.

Can you change the language of the InBody App?

The languages on the app are English, Dutch, Vietnamese, Portuguese, Italian, Thai, and Chinese (Madarin).

Can I see my test results on a computer, such as a MacBook? Is there software to facilitate this? Can I print my results via the App?

The InBody App uses Bluetooth technology to connect to your iPhone. Software is provided to facilitate this feature. Printing functions are enabled via the App.