The official American Express app for Windows Phone is currently not visible in the Windows Store when a search is conducted. The credit card company says it is aware of the problem.
Several Windows Central readers have tipped us to this problem. When contacted via Twitter, an AMEX rep told us they are aware of this issue but did not offer any word on when it might be fixed
@jcalmn Hello John, thx for reaching out to us. We have been made aware of the issue. There is no current update at this time.— Ask Amex (@AskAmex) June 24, 2016
The app itself is still available via direct download at the link below.
Thanks again to all of the tips!