 The iPad syncs with iTunes on a Mac or Windows PC . Apple ported its iWork suite from the Mac to the iPad , and sells pared @-@ down versions of Pages , Numbers , and Keynote apps in the App Store . Although the iPad is not designed to replace a mobile phone , a user can use a wired headset or the built @-@ in speaker and microphone to place phone calls over Wi @-@ Fi or 3G using a VoIP application . 
