Msg2india - send sms to India using Way2sms is a Browser software developed by Maulik Gandhi. After our trial and test, the software is proved to be official, secure and free. Here is the official description for Msg2india - send sms to India using Way2sms:

You can send Free SMS to India using Way2sms.com without opening that website.You can Send SMS upto 140 characters.

Just Install this extension and click the icon seen beside adderssbar (see in the screenshot).
If you want to store contacts, send sms to many, or want to remember mobile number and password then just click on "Open in new tab" button seen in pop up.