You are able to add a logo to your generic PDF reports.
You can do this on an account level (which will use the same logo for all forms), or on an individual form level.
For setting up your account level logo:
1) Select "Account" on the top Menu
2) Select "Branding" under Account Settings (left Side)
3) "Browse" and Add a custom Logo
4) Be sure to hit the "save" button
As mentioned you can also setup a custom logo on the form level.
1) Open your form and click the "reporting" button in the top menu bar.
2) "Browse" and add a custom logo.
3) Be sure to hit "save".