Connecting Korg Volca Bass with iPad- IOS apps

[DannyDarko]

I would like to connect the Volca Bass with my iPad so that I can make use of AMPS & FX apps like ToneStack and AmpliTube. (I want to mess around with delay FX, like ToneStack's 'Cosmic Echo'). To be clear, I want the sound of the Korg go through the iPad and use the software FX of various stompboxes to add delay, echo, EQ and so on. I also would like to ability record everything on the iPad in the highest possible quality. I understand there is the iRig2, but this is for guitars, and I understood that it will give overdrive if I use the standard iRig. And I wonder if this will give the best sound quality. I spoke with a guy from a music store and he recommended me the IK Multimedia iRig Pro Duo ( http://www.ikmultimedia.com/products/irigproduo/ ).
He told me that the only way to attach the Korg to the iRig Pro Duo was using a jack 3.5mm stereo - 2x jack male 1.5m cable ( https://www.bax-shop.co.uk/jack-jack/de ... 1-5m-cable) from Korg Volca the headphone port to the iRig. I would like to double check with you guys if this is all correct information, as the iRig Pro Duo is not cheap. Do I need the Duo option, will the single Pro not work well? Also, is the headphone port on the Volca the only way out? Will I not get the overdrive with the Pro Duo?