The file should have three columns. The first column represents the recipient's phone number (format this column as a text, otherwise leading zeros are removed by Excel). The second column represents the recipient's name. The third column is the actual message to be sent to this recipient.
Note 1: this application should not be used to send spam. It was primarily created as a modality to greet people you know at holiday time: Christmas, Easter, etc.
Note 2: sending SMS might cost you money. Please check with your mobile carrier to find out more details.
Note 3: a SMS message can contain up to 160 characters. Longer messages are sent in chunks and thus you end up using more SMS to deliver a single message.
Note 4: Android devices have a built-in protection against sending many SMS in a short period of time. The user is informed by a pop-up that SMS are sent from his/her device. To prevent that pop-up to appear, the SMSMachine has a delay of 3 seconds before sending a new SMS. Thus, in an hour frame, the application can send up to 1200 messages.