Simple tip for Kali Nethunter:
You don't have to run any mana or karma, hostapd or use an external WiFi adapter for credential harvesting. Just openly share your normal WiFi access point and run the net-creds.py tool that comes with mana. Any unencrypted creds will be caught and stored.
Important: don't do this in public unless you are willing to risk being arrested. Also be aware that when you share your WiFi for open tethering, you may be incriminated for the actions of anyone who connects.