I have played a bit more with my ipad/iphone at home. The worst thing of all is that you can not really know if these devices changed access point because there is no indication on what wifi channel they are. Your only indication is the 3 level :) wifi strength bar which even in laptops it not very accurate. Worst of all apple disabled the wifi card API and so there are no apps available to tell you on which wifi channel you are. Some apps do exist but the "i" device must be jailbrocken to use them.
The only half-way I have found to see if I am indeed roaming and changing channels is having the APs' client list open and see if they change but in most APs this is not very dynamic and hence does not work well. Am I missing something, is there a way to test roaming on the ipad/iphone?
P.S. On laptops I test this using inssider, and you can very clearly see when you changed channel and hence AP.
