It's probably the tracker, not the app update, just one of those correlated but not causational things. Mine worked fine for years, tracked steps, still charges, and tracks but can't add it to Fitbit. Bought another off eBay and was able to add it right away. I'd questioned similarly as also experienced an app update, but as the new One was able to be added it's clearly something malfunctioning in the unit itself. I'd even tried removing the newer One and went to add the old one back, fully charged, and it won't. It will get to some point saying it's connecting to the Internet and fails. I turn on the new One and it detects it right away. Fortunately, Ones are readily available on eBay. Cheers!
