If you mean would the app be compatible with the EZ-220, I think so.
The EZ-220 has a USB-MIDI (or "USB TO HOST") port rather than MIDI ports, so to connect to an iPad or iPhone you'll need a standard USB 2.0 printer cable. If you prop up the iPad on the keyboard's music rest then a short cable is ideal (no excess hanging down behind the keyboard); I use a 2-foot cable.
You'll also need a "Camera Connection Kit" or something similar for your particular model of iPad. The older Camera Connection Kit was for connecting a USB device (such as a camera with a USB connection, or in this case a musical keyboard with a USB connection) to an iPad having the older 30-pin connector port. The newer version is for connecting to an iPad having the Lightning port.
The "Sound Controller" app cannot do anything that your keyboard isn't capable of. Fortunately, that refers to the types of MIDI messages that the keyboard can respond to, and not simply the functions that are accessible via the keyboard's panel controls.
For example, the EZ-220 doesn't have a Pitch Bend Wheel or a Modulation Wheel, yet it does respond to MIDI Pitch Bend messages and Modulation messages, therefore you can use the app's virtual Pitch Bend Wheel and Modulation Wheel to bend notes as on a guitar or add vibrato to them.
The EZ-220 also does not have functions or controls for editing the Attack Time and Release Time of a voice, yet it does respond to MIDI Attack Time messages and Release Time messages, therefore you can modify the sound of a voice by changing its attack/release settings.
And the EZ-220 doesn't have functions or controls for editing the Cutoff Frequency and Resonance of the LPF (low-pass filter), yet it does respond to those MIDI messages, therefore you can modify the cutoff/resonance settings of the filter to get interesting results.