Login to your Bitfinex account, hover your profile icon on top right and click API Keys from dropdown menu.
Click on Create New Key
Now, label your API key with any label you'd like to (we recommend to use a separate API key for each service you use and label them accordingly), make sure to give permission to "Wallets" and click on "Generate API key"
You need to check your email and go through the link
After clicking on the link sent via email, you will see a screen with QR code, your API Key and API Secret. Like below
Now go to CoinStats app Portfolio tab, swipe far to the right, click Connect Exchange and select Bitfinex from the list.
Click QR and scan the QR code presented by Bitfinex or copy/past your API Key and API Secret Manually.
After clicking Submit you will see your Bitfinex portfolio synced with the CoinStats app.
Refer to support in case of further questions. Hope you'll enjoy!