How to setup Exchange or Google mail, calendar, contacts using ActiveSync on your iPhone or iPad
Exchange is Microsoft's corporate email, calendar, and contact system, and ActiveSync is their fairly awesome protocol to keep it all updated on all of your devices, including iPhone and iPad. Google licenses ActiveSync for Google Sync, which used to be available for all Gmail accounts but is now restricted to paid Google accounts. No matter whether you use Exchange directly from Microsoft, from Google, or from your company or a third-party service, it's all setup the same way. All you need to know are your credentials.
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