Hi Bill. What determines what is allowed and what is not, is clearly defined in the rules that are agreed upon, on the same page where you place the ad:
https://swap.qth.com/add-step1.php
If you see someone selling watches, I suspect the ad would be quickly deleted by our volunteers but, if not, please let us know... we would welcome your help! My email is linked at the bottom of every page of the classifieds.
iPads could be used for ham radio -- FlexRadio owners can certainly attest to how useful running their stations remotely via iPad can be.
If your drone is useful to ham radio, then please state this in the ad, so that it will not be removed. That said, if you posted the drone FOR TRADE, it would have been allowed, and not removed. Please contact me directly to discuss this issue further.
73 - Scott KA9FOX