You wish to attract your customers to your stores.
The traffic in your store is low. As you know, the only way to increase your sales is to attract your customers via promotions and discounts and all you need is to inform them quickly and in a low cost way. So you sit in front of your computer and send all your customers the following SMS: "Only for this week and especially for you 15% discount on all our products. Code Z158."
Use Web2SMS service that allows you to send SMS and MMS easily, quickly and at a very low cost.