I just realized that I sent an email from my g-mail app on my iPad signed "sent from my iPhone". So I reset my iPad signature to "sent from my iPad". Guess what? An email Is sent from my iPhone g-mail app was signed "sent from my iPad". Does anybody have a fix aside from just using the signature "sent from my iPhone/iPad"?
The Gmail app syncs your signature to your account, not just your device. One solution would be to use the Gmail app on one device, and the default Mail app on the other. The Mail app stores the signature only on your device, so you can keep it separate from the one synced to your Gmail account.