You have motion detection enabled in icamsource? Do you also have push notifications enabled so you'll receive notification of that motion? If you want the motion events to be recorded, that's yet another option that you can enable. If you don't have either/both push notifications and record motion events enabled, the only way to tell that motion detection is working (as far as I know) is to view the video feed in the iCam app....while zoomed in on one camera (and tap once to see the menu options), you'll see the round "motion" light flash green.
If it's still not working, you might want to clear the icamsource preferences and set it up from scratch. This often fixes issues like this. Are you using Windows or Mac? The directions for clearing the preferences depend on your operating system.