iPhone, iPod Touch and Windows Mobile phones support Push Gmail
Google brought Push Mail support to its Gmail service using Google Sync for iPhone platform, Symbain and Windows Mobile based devices. Earlier this year, Google had introduced Google Sync to synchronize Gmail Contacts and Google Calendar with S60 devices, Windows Mobile and iPhone. It's Google who brought Push Gmail to the iPhone platform. Note that iPhone or iPod Touch need to have iPhone OS 3.0 version or higher running on the device.
Google Sync is a service that allows users to synchronize their Google Contacts, Gmail and Calendar to mobile devices using Google Account. By setting up Google Sync on iPhone, iPod Touch or Windows Mobile phones, users can get Gmail messages pushed directly to respective devices. This means that the user's Inbox on iPhone/Windows Mobile phone is always up to date. Also, address book can be accessed anytime.
Take note of two things before jumping to setup Google Sync. Firstly, Google Sync uses Microsoft Exchange ActiveSync Protocol for setting up Google Sync on the device. Also, ActiveSync supports only one profile so if you have one account activated on Microsoft Exchange on your phone, second one can't be added.
Backup the existing data for it's likely that it might be wiped out. Secondly, Push technology is known for being power intensive and enabling Push notifications on iPhone may reduce its battery life.
To activate Google Sync service on iPhone/iPod Touch, check the setup instructions here and Windows Mobile users can check here.
In this cold war between Google and Apple, the former has just scored a brownie point by releasing the feature that Apple promised year ago.
Gmail and its message push are native on the iPhone and have been for years, what's new about Gmail on my phone?
I'm actually shocked it's taken so long to start syncing my phone's contacts and calendar events with my Google accounts over the air, but if this works, better late than never.
For a real "killer app"- Google should implement ActiveSync in Gmail TO Exchange servers. Gmail/GoogleApps is SO much better than Outlook, and using SMTP/POP is archaic these days.