Login to your Coinbase Pro account, click on your Profile icon on top right and select API.
Click on + New API Key
In Add An API Key box fill in API Key nickname field (ex. CoinStats Coinbase Pro), give permission to View and save your Passphrase. After click on Create API Key.
Enter 2-step verification code and click Add an API Key
You will see a screen like below with your API Secret key.
Please make sure to copy/paste your Secret Key to a safe place, as it will only be displayed at the time it is created. If you lose this key, you will need to delete your API and set up a new one.
Now go to CoinStats app Portfolio tab, swipe far to the right and click Connect Exchange.
Select Coinbase Pro from the list and paste your API Key, API Secret and Passphrase.
After clicking Submit you will see your Coinbase Pro portfolio synced with the CoinStats app.
Refer to support in case of further questions. Hope you'll enjoy!