A User of Ancoris Signatures
I tested this and didn't like a few nuances of how signatures are configured. Also, the user can add their own signature line in Gmail, Thunderbird, Outlook, etc. and it will display above the added signature. Not for me, so I revoked its access and deleted the app. Appogee still inserted signatures into my emails. I disabled API provisioning for my entire Google Apps domain. Appogee STILL is inserting signatures in my emails, and I don't even have the Provisioning API enabled in Google Apps anymore! I then re-installed and enabled it, make a blank signature template, updated the affected account with that, then "removed" those accounts via the Appogee application control panel, and IT STILL adds that unwanted signature in ALL of my emails! Way to latch on to someone's account and NEVER let go, developers. Beware of the permissions you give this.