Been to HK several times. Was just there last month. Took my cellphone and work computer (and across my family we had 3 cellphones, 4 ipads, a laptop and a kindle). Did not do anything special other than enabling my wife and son's phone for international travel day pass! I work for a large global company -- we have protocols for mainland but not HK (though maybe we will for HK too in the future reading the article linked above about the major consulting companies).