SMS Scheduler is a simple but effective SMS scheduling application, which with you can schedule outgoing SMS messages with timer, either to be sent once, or with different repeat options.

定时短信是一个简单有效的短信调度应用程序。您可以安排使用消息计时器传出短信，选择发送一次，或者重复发送。

youdao

The company reported its youth-oriented brand, Hi, saw an 8% decline in outgoing SMS or text messages per customer in the first three months of this year compared with the first quarter of 2010.

WSJ: Cellphone Carriers Face Pressure Over Texting

Geva Rechav, a Google product manager for emerging markets, confirmed in a blog post that Gmail SMS messages will be free to receive, but standard fees will apply for outgoing emails.

ENGADGET: Google launches Gmail SMS for text-based email in Ghana, Nigeria and Kenya