I found myself 2 hours from home without my wallet, tired and with a hungry daughter in tow. No wallet? No problem. My Coffee Card, the unofficial android version of the Starbucks card, bought lunch, dessert and my favorite venti peppermint latte with no cash needed.
I was a bit a skeptical of the app’s unofficial status at first, but it has proven to work perfectly with my Starbucks account so far. Download it from the app store to get started: http://market.android.com/details?id=com.birbeck.starbuckscard. The free version has no ads or nagging pleas to upgrade. So I upgraded anyway to support the developer. The My Coffee Card Pro version ads the ability to add multiple Starbucks cards.
Baristas are not supposed to touch your phone, but they have a handheld scanner that they can use to complete the transaction. It does make drive through transactions difficult, though, so I usually walk inside the store.
When you register your Starbucks card at https://www.starbucks.com/card, you can also set up automatic reloading so that your Starbucks card (and your app by extension) never run out of funds. You can also reload the card manually with a credit card from inside the app itself.
My Coffee Card also offers a widget ad part of the app download so that users can see their card balance, their rewards level and get one-tap access to their barcode.