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Sms

Try GlobalAQ, download the free version and test if it supports your target network.
 
I believe you get the choice to either use your existing mobile number or to have a new one generated by FishText (for privacy reasons I guess)
 
Facebook.

Facebook have an SMS service that you can subscribe to. Once registered to the SMS notifications whenever you get a comment or message from FB they text it to your phone.

It might be worth a shot, its free for users to recieve SMS updates and all you do is send the message via the facebook website or iPhone application and FB send that message in a SMS message to the recipient
 
O2

My girlfriend was recently in Aus and New Zealand. I added a family bolt on for £7.50 which give me free texts to her. (It's only meant to work in the uk) Also she noticed while away backpacking if she sent exactly 160 characters i.e 1 text message not one digit short or longer she never got charged. She was there for 3 months and I think the only thing we paid for was the family bolt on.

Might be of some use for you. Could have been a lot more expensive. also worked if grouping 2 or 3 msgs together but never go over the full characters for 2 or 3 texts consecutively then.


She was on o2 pay as you go with a non iphone phone
 
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