Hi @brent, welcome to the Cayenne Community.
Right now the iOS app is logged into your Cayenne account continuously, so in that sense if your iOS device is locked with Touch ID, then your Cayenne account would be too. But we don't have any Touch ID feature built specifically into the app at this time. For additional security you could log out of the Cayenne app when not in use, but you'd have to log back in with email address and password.
It's a good suggestion though, I'll log it on our roadmap for future discussion with our Product team