iOS settings and restrictions might work differently for the app. If you can't see your calls logged, check out for these settings.
✔︎ First, make sure your Salestrail call logging mode is set automatic.
✔︎ Then, if you make calls from outside Salestrail app or use your iPhone dialer, go to Unlogged Activities.
Here, you should be able to see all the calls you have made on both your iPhone dialer and inside Salestrail app. Tap on any to log your calls.