I am considering moving to an iPhone from Android, and I'm wondering how well it works with Gmail. Is it as good as Android? In particular, I love the way that contacts and calendar work with with my Android phone - I update/add a contact or calendar item from my phone, it immediately updates Gmail online, and the same goes for the other way around. Can the iPhone do this as well?
Also, are there apps for email like on Android (currently use Touchdown for Exchange (my work) email and K9 mail for home email), or do you have to use the built-in email app?
GMail works well on the iPhone. I have a Verizon iPhone4 setup with my Gmail contacts through a CardDav account. I have my emails come through the GMail setup built into the phone. I used to have everything setup through the Exchange setup but once the CardDav method was available I switched everything over. I also have my calendar setup through GMail.
I used to keep everything through iCloud on the phone, but I changed everything over to Google Syncing as that was where everything has been for me since day one.