Core Shell has been working great for me on my MacBook so I installed the iOS version. It's syncing via iCloud and I've added my keys to the app. Two of the servers work great but I've always received a 'Abnormal Disconnect' on the third.
This is the log:
Equivalent Command: ssh -i /private/var/mobile/Containers/Shared/AppGroup/41BE8BDF-F8B1-4DAE-81FF-966AF2D820B5/.ssh/KEY -o ExitOnForwardFailure=yes -o ServerAliveCountMax=3 -o ServerAliveInterval=15 -o CertificateFile=/private/var/mobile/Containers/Shared/AppGroup/41BE8BDF-F8B1-4DAE-81FF-966AF2D820B5/.ssh/KEY -p 37980 root@XXX.XXX.XX.X
18:52:39 Connecting...
18:52:39 Authenticating...
18:52:39 root@XXX.XXX.XX.X: Permission denied (publickey,gssapi-keyex,gssapi-with-mic).
18:52:39 Abnormal Disconnect