The ability for companies to follow you from one platform to another — from your phone to your laptop to a physical store — is called cross-device tracking, and for businesses that want to market and sell stuff to you, it is basically the holy grail.

With robust tracking, a company can follow you basically from the moment you wake up and check social media feeds on your phone, through your commute, to work, back through the evening, and once more to your bed at night.
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To get there, the FTC recently held a workshop on Cross-Device tracking, and has now published a report [PDF] highlighting some key facts about this increasingly popular practice.

Source: 5 Things We’ve Learned About How Companies Track You Online And Off – Consumerist

1. You don’t need always to be logged in to be tracked.
2. Cross-device tracking can actually improve account security.
3. Companies are not at all transparent about tracking practices.
4. Consumers have very little control.
5. The industry is working on some voluntary self-regulation… sort of.