Normally I would just blindly advise you how BAD it is to use the ebay mobile app. But why not just read a portion of their ToS contract that you accept after you install the app on your phone and you can see why it is a bad, bad idea to use it. Quote:
PRIVACY POLICY
This policy applies to your use of the Service and tells you how we use and protect the information we collect.
Collection and Use.When you use the Service, we may collect and store some or all of the following, for the purpose of providing you the eBay Now user experience:
Device sign-on data (including device ID)
Location data
Keywords and search history
Your email address and correspondence sent via the Service
Payment method information (including card number, cardholder name, billing address, billing telephone number)
Information about how you interact with the Service and eBay's properties
We and our service providers use this information to operate and improve our applications, sites, services, and tools.
Sharing Information and Tracking. We may use third parties to provide parts of our services as well as to provide analytical data about your use of the Service back to us. We may deploy devices such as cookies that enable those third parties to anonymously collect and aggregate usage data and report it back to us. Third parties that we contract with to help provide our services cannot use your personal information for their own purposes without your explicit consent.
| You want to avoid using this app at all cost if you plan on using stealth accounts. If, however, you want to use it...then you run the major risk of linking accounts.
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