I wonder if this software allows me to send one text to 400 mobile phones (belonging to our local union members) from PC through my mobile using the unlimited SMS plan that I currently have or I need to buy credit to do this?
Yes. By using this product you can send up to 800 SMS messages per hour. This is done using your current mobile plan. If you have unlimited text messages, you won't need to purchase additional credit to send your messages. You can find more information on the official website.