Which app method is efficient to create third party integration applications(connect or forge)?

Hai @remie @dmorrow
What about to encrypt the API key and split the private key and the encrypted token into two different locations (private key into user properties and the encrypted token into DB) that way it can be more secure by making sure only the app has access to both the locations. Is this efficient to my requirements? Is it possible to do like this?
I don’t have any option. That’s why i chose to use own DB.