Our first impressions were that Roland's new Aira Modular effects sound pretty impressive right out of the box, but if you want to set about tweaking their signal paths, you're going to want to take a look at the company's new Aira Modular Customizer software.
Available for PC, Mac, and iOS/Android mobile devices, this enables you to fully re-program the internal signal paths of Roland's new Eurorack-friendly devices (Torcido, Bitrazer, Demora and Scooper). In each case, an array of 15 virtual sub-modules is available, which you can patch together on a graphical interface.
Re-patching can be done in real time; just connect the headphone jack of your smartphone or tablet to the Remote In jack on one of the modules (making sure the volume is at its maximum level) and you can get busy.
You can find out more and get download links to all versions of the app (which is free) on the Roland website.