The Australian Communications and Media Authority (ACMA) has fined Optus for an SMS campaign promoting its mobile entertainment services.
It did not clearly identify itself.
Hence, be clear about your marketing message and ensure you comply to international and local government laws as well.
Please find the link to the Mobile Marketing Association – code of conduct:
http://www.mmaglobal.com/policies/code-of-conduct

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As yahoo in recent years have fallen behind Google in terms of technology has just unveiled its mobile web platform to regain some position in this space.
Yahoo hopes the mini-applications, known as “widgets,” will help attract more on-the-go users, which will bring the company more money from advertising.
 Yahoo!, released an upgrade to its “Go” software [...]