Any generic 2G/3G USB Data Card from Hauwei or ZTE or Netgear or DLink which shouldn't cost more than 30$ - 40$
Check this link
http://www.flipkart.com/computers/network-components/data-ca...
Is there any reason to use twilio over something like this? Twilio costs 0.0075 / message
Ting charges $6/device plus $0.0025 per message.
Twilio's pricing schemes change per country, for us in India (where 1 Rupee = 100 Paisa and USD 1 = ~62 Rupees), twilio charges 60 paisa per message. At the same time, some tel-com providers have plans that cost only 5 paisa per message. India has other limits and regulations but for personal/in-house use they hardly matter.