The iphone was bleeding edge... Of you disregard Neonode. But that is the only that comes to mind. The other bleeding edge has been the overall ecosystem around its product.
Numerous smart phones existed with email, text, call, and internet. iPhone just made it infinitely better. They also had the advantage of convincing carriers to start making money off data rather than text/minutes. This was a paradigm shift that allowed for full web browser to exist. It guzzled data, so carriers were fine subsidizing the phones and reap profits of data plans.