The mantra of Walgreen Co. is convenience. And the drugstore chain has built mobile apps and a text message program that aim to make shopping at Walgreens, through mobile or in stores, as convenient as possible.

Customers are responding in droves. Less than four months after introducing Refill by Scan in its iPhone and Android apps, more than half of all prescription refills ordered through mobile are scanned, the company says. The feature enables app users to hold a smartphone camera above the bar code on a prescription bottle and have a refill order automatically created, an order which they can complete with one touch. The process takes seconds.

On another mobile front, customers can elect to have notifications that their prescriptions are ready to be picked up sent to them via text message. Today more than one million customers have subscribed to these alerts, which were introduced in March 2010, says Walgreens, No. 68 in the Internet Retailer Top 500 Guide.

“Our customers have enthusiastically adopted our mobile applications and we’re continuing to bring innovative technology to our online and mobile platforms to enhance the customer experience,” says Sona Chawla, president of e-commerce. “With Refill by Scan, prescription text alerts, unique photo features, and the ability to shop or browse products all available on a mobile device, we’re adding new levels of choice, control and convenience for our rapidly growing numbers of mobile customers.” Walgreens is highlighting its suite of mobile services and the Refill by Scan technology with a new advertising campaign. The Walgreens mobile app has a 4.5-star rating in the iTunes Store and a 4-star rating in the Android Market. The application is free and available for download in both app stores.

Chawla will be speaking at the Internet Retailer Conference & Exhibition 2011 , June 14-17 in San Diego in a session entitled “Mobile, web, stores: Coordinating all channels to capture today’s always-on consumer.”