You can either link with your Fitbit Aria Scale on My Fitdigits or in the iOS version of Fitdigits vwithin the app so you can see your weight entries on My Fitdigits.
My Fitdigits
1. Login to My.Fitdigits.com with your Fitdigits username and password.
2. Tap Health -> Activity -> Link Accounts.
3. Enter your Fitbit login/email and password to authorize the link.
In App
1. Tap Health -> Health Partners
2. Tap Fitbit -> Link Account
3. Enter in your email address and password, and tap allow
Enter in your Fitbit login and password, and tap Allow
Tap Link Account
4. Tap Done in the upper right. Your account is now linked!
You now will see your Fitbit Aria weights on My Fitdigits!