Each person who downloads the Wearsafe App, with or without the ability to send alerts, must sign up for their own account. This way it ensures that the information communicated in an alert is accurate to the person who sent it.
You can have multiple Tags per account, but not multiple accounts per Tag. And we suggest you download the app for the first time on the mobile phone you will be using with Wearsafe. It is meant to be mobile after all!