If you connect the looper to an aux send on your mixer, you can feed the looper any source from the mixer. Very flexible, but you have to pay attention to your sources, levels, effects etc.
Using a pre fader send, you can prepare loops regardless of the mixer levels of that instrument. You could capture a synth loop and then fade it into the mix, then capture another loop or use the synth for something else.
You could plug the looper into a channel on your mixer which would let you make use of the eq and effects sends.
You can also use the looper for transitions. My H9 looper has a dry/wet control, so I can fade from the dry signal to the loop playback. Very handy.
Some loopers offer midi sync, the H9 looper syncs perfectly to midi clock. You can configure it so that when you press the record footswitch, it will start recording at the next bar. You can also set it to autoplayback after a set recording length. So capturing loops for tranditions is as easy as on the Octatrack.
Or you can feed an instrument directly into the looper and use it primarily as a source for building loops and textures.
Put a filter after the looper, put effects after the looper…
If you want to know if a looper fits your workflow, which features you need and which you don’t need, you can play around in your DAW.