It's actually midway between both the scenarios described by you. You definitely need to make a Tata play Binge account and most of the OTTs' content will play within the Tata Play Binge app, but some major OTTs like Disney+ Hotstar, Zee5, Sony LIV, Jio Cinema etc will redirect to their respective apps which you will need to have installed on your device. Once you are directed to those apps from Tata Play Binge and login with the same number as that registered on Tata Play Binge, you will get the subscription of those OTTs activated in those apps. Later you can even access those apps directly, you need not always launch Tata Play Binge to play that content.