Ameritrade and Tradier Brokerage are easy to interface. In the Option Stalker Pro, log in then in the pop-up select the appropriate broker in the drop-down menu. During the interface, these brokerage firms will ask you to provide your login credentials for their website and the interface will be complete.
The Interactive Brokers interface is a little more complicated because you have to configure their API in Trader WorkStation (TWS). Find Edit in TWS in the upper left corner and follow this path. Edit/Global Configuration/API/Settings. Once you have done that mark the first box (Enable ActiveX) and make sure that Read‑Only is NOT marked. Click OK. You only have to do this once. We suggest logging in to Interactive Brokers TWS and then launching Option Stalker (Pro). In the Option Stalker (Pro) login pop-up, you will see Interactive Brokers listed in the drop-down menu. Once you launch Option Stalker Pro they will automatically connect. For more information on the Interactive Brokers API, please go to the bottom of this FAQ page.