Hi M P,
What drone are you flying?
The different setup/configuration that Pix4Dcapture can support are listed here.
By having a closer look at it, you will see that Zenmuse Z30 camera is not compatible with our application. Your second camera is most probably not supported too.
Also, we have no experience with the Pixhawk controller as we did not test it, it is then not officially supported and we can not tell you if it can work or not with our application. In any case, we would suggest using the standard controller associated to your drone.
About the DJI A3 flight controller, as it is a device associated with your drone to make it more reliable, I have no reason to believe that it would interact with Pix4Dcapture. However, we did not have any chance to test it either so we can not make any guarantee that you will be able to fly properly using Pix4Dcapture with this device embedded on your drone.
However, If your configuration is supported and up to what you need, on the iOS version of Pix4Dcapture you can set a custom camera. The procedure on how to set it is described here. The important step is to define the time-lapse directly in the settings of the camera, and then apply the same value for the Min. triggering interval [s] in the application. If not, the camera will not take any picture as it cannot be controlled by Pix4Dcapture.