Assuming your iPad only has USB-C or Lightning or whatever, (and you're recording on your laptop-? Not sure if I've got that wrong...) you just need the dongle to output a 1/8" audio jack. Get a 1/8" -> split 1/4" stereo cable. You can record the tracks into your DAW first, then overdub your bass. If you *need* to do both at once for whatever reason, then pan everything in your backing track app to the right and just plug the right end of the split 1/4" into one input on your interface, and your bass into the other input.My interface has two inputs. They can accept mic level and instrument level. I don't know of any type of cable that could plug into my iPad on one end and the interface on the other, but perhaps there is. However, I will be trying to run an iPad type cable from the iPad to my Microsoft laptop, as was suggested above. After I've had a chance to try it I will report back. Thanks again.