Can I use the Tidal app for streaming with node 2 without Bluesound app?

Unfortunately, as djones51 mentioned, it is not possible to stream to Node2 directly from Tidal's native app. Same issue with Amazon. If you don't like the BlueOS interface, you can try Roon. It is an additional $10 per month but the features and the ease of use is by far the best that I have experienced. If you also use Spotify, Roon provides a one-stop shop for all the major streaming services.

At any rate, bluetooth is never going to compete sonically with wifi or ethernet.

Ok now I get it. Bummer - I like the concept of "radio stations" and "Daily Mix" that both Spotify and Tidal offer on their Apps. As far as I discovered so far, Bluesound is much more basic than these sites. Need to reconsider the design-up to Tidal.

@arafiq : It was my understanding that the node 2 and the iPad have to be connected to the same WiFi network. The node2 streams via WiFi or LAN and Bluetooth between Node 2 and the iPad is used as a GUI/navigation aid similar to a remote control. Am I wrong? Your description sounds as if the streaming "receiver" is the iPad and the iPad is sending the signal to the node2 via Bluetooth. Strange...?

As long as you’re on the same network you can use the tablet to control the Node2 with bluOS you don’t need bluetooth. I’m not 100% sure as I never used bluetooth can’t stand it, but I think if you use the Tidal app on the tablet and send to the Node you’re getting the stream through wifi to the tablet then sending the stream through bluetooth to the Node which might be down sampling. If it’s the Node2i you can use Airplay2 if your tablet is an iPad that supports it.

I finally figured it out how to connect without BT - Thanks! 
@djones51: I believe you are correct with the Bluetooth down sampling but at first listening I do not hear such a big difference so perhaps convenience is worth the small loss?