Cache only add-in.   ACT! Premium Cloud does not allow for screen popping of Contacts.  Screen popping of Companies is possible, however ACT! Premium Cloud only supports Google Chrome.    International numbers are not supported due to limitations of the ACT! Premium Cloud API.  For address book searching there are the following limitations•               When searching by name, only searches with one word or full name are possible.•               Searching by Address, email or notes are not possible 

If the integration supports caching, please note that cached integrations support up to 30,000 contacts. The live mode method would need to be used for larger directories. Performance will then be determined by a number of additional factors including network speed and application API specification.