IPad – How to send text messages to non apple devices from an iPad

iMessage is actually an instant messaging service, like Google Talk or AOL Instant Messenger, except iMessage is made by Apple and is only for Apple products. Only an iPhone with cellular can send SMS messages as well, and can automatically associate phone numbers of registered iMessage users with iMessage accounts, so if you try to use the app to send a text to a phone number registered to an iPhone, it will send an iMessage instead. iPads cannot send SMS messages to non-Apple devices nor an iMessage to a phone number not registered with iMessage from a Wi-Fi-only device.

http://support.apple.com/kb/HT3529

Try IFTTT. This lets you set up recipes that can do things, such as send an SMS when an email is received. The contents of the SMS can be customised based on the contents of the email, such as including the subject and/or body of the email in the SMS.

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