Example, max range on the vJoy joystick is much greater than on XInput joystick. Need to re-scale the XInput joystick values.

The RC filter is simple and works well for smoothing the signal, but introduces a significant lag. It was most noticeable using the VR Joystick Strafe mode, where device orientation determines which direction the character is moving. Device orientation depends on the user's real-world orientation, but also on additional device movement induced by running in place (noise).

More complicated filters have been designed to minimize the lag, e.g., the Butterworth filter. No filter is perfect and there is always a tradeoff between smoothness and lag. For our purposes, the "noise" that needs to be smoothed/eliminated arises from the device moving inside of the user's pocket, and from natural leg motions that aren't perfectly forward-backward but have a rotational component.

Filters that need the entire signal, or even more than one to a few observations at a time, are not useful for our purposes because we need the filter to work in real time.

App should check for updates on startup and prompt user to download.

On gamepad mode, X, Y, RX, RY, Z, and RZ sens are too low. Mouse sensitivity is too high on Mouse mode.

Assuming almost all packets are eventually delivered, the biggest source of error is receiving packets out of order. We could stamp each packet with an int that goes from say 0 to 999 (to save on packet length) and then resets. This behavior should be implemented using the modulo operator on the CoreMotion loop counter in iOS (t%1000). If CFW receives a packet with stamp smaller than the last one it got, it simply does not use its data (unless the difference is large, say >900, which would indicate that the counter reset).