Two recent announcements prove that retailers are very much in the mobile payments game. First, The Wall Street Journal reported that Walmart and Target were among two dozen retailers collaborating on a mobile commerce project. Then, Starbucks shared the impressive numbers from its Starbucks Mobile app, which launched in the U.S. in January 2011, and the UK and Canada a year later. 42 million: that’s how many transactions the company has processed in the 15 months since it launched, and 16 million of those happened between December and April.

Retailers aren’t waiting for NFC, or for banks or Google Wallet—or permission. They’re getting ahead and launching their own systems. And why not? They’re seizing the opportunity to take control of the customer relationship, which they already own, in a new channel.

The Starbucks Mobile app is a great example of what it takes to succeed with mobile commerce and mobile CRM. It’s not fancy or complicated. It’s simply a digital version of the coffee giant’s existing loyalty card, already popular with millions of customers. Load funds to the mobile app starting with a prepaid card and then a credit card, bring your phone to any Starbucks in the U.S., UK or Canada (it works across countries), and scan the barcode at the register after selecting your coffee. Simple, and here’s the key: more convenient and rewarding than cash or credit. (Though the loyalty aspect, which only applies to U.S. customers, requires a hefty 45 purchases to receive your first free drink, it only takes 15 to earn them thereafter.)

Once a company has a successful mobile payment method, it’s a short road to mobile loyalty and engagement programs. Not only do retailers have a direct marketing channel for sending offers, coupons, alerts and reminders, they also receive detailed information about each customers’ purchasing behavior.

The two-way communication that’s possible with mobile means retailers and brands can truly know their customers, and deliver the right message at the right time to the right person. “Haven’t seen you in a while, Mr. Talbot. Come back in for 15 percent off this month’s signature drink.”

Retailers understand that making the most of mobile means tying it into what they already do, enhancing every stage of the customer lifecycle.