The iPhone did what it could do because it bundled a data plan that was reasonable at the time ($20/month unlimited, though 2G only, was a pretty damn good deal). Prior to my iPhone I used a Treo 6xx series that Verizon wanted me to pay $45/m for data (2G also).

The lack of native data connectivity made PDAs deal with the continually nasty and ever under-estimated problem of sync. With iPhoneOS v1, Apple matched what Palm had to offer - an iPod touch was almost as good as a Palm PDA, an iPhone better than a Treo. With iOS2 and ActiveSync, it blew away it's competition.