I have not yet done API programming, but I plan on starting soon. I gather that IB requires a client-side component (either TWS or Gateway) as an intermediary between an API client (my programming logic) and IB's servers. Whereas the Schwab API for example, if I'm not mistaken, doesn't require a client side component to run i.e. I can directly program a client and run it against Schwab's servers; let alone a component that needs to be periodically restarted, which seems to be a major hassle. Is there any logical reason for IB's approach?