I'm new to Zoho Mail and am about to set up a new Mac computer, iPhone, and iPad. I would like to sync mail, contacts, and calendar across all three devices. In reading the forums and user manuals, there seems to be two approaches: 1) use the Zoho app on all three devises, or 2) use Zoho Synch to perform wireless synchronization of Zoho application with built-in iPhone/iPad mail, contacts, and calendar applications. 

My questions: 

* Does anyone have advice about which approach works best in terms of user friendliness, timely synching, lack of glitches etc.?

* With both approaches, can mail, contacts, and calendar be accessed when the device is NOT connected to the cloud (whether via WiFi or cell service)?

* With both approaches, is it possible to backup contacts to an external hard drive? (I've found instruction for backing up mail and calendar to a hard drive, but not contacts)

Any other advice about which approach works best would be appreciated! Thanks.