Lemon , creator of the Smarter Wallet  app that lets you store digitized versions of the paper and plastic bits in your wallet, just launched Lemonade , a platform for third-party publishers to create add-ons to the digital wallet service.
With Lemon's Smarter Wallet users can store all the things you'd normally keep in your wallet, including credit and debit cards, loyalty cards, coupons and receipts, and even your driver's license and health insurance card. The app encrypts all your data and requires a four-digit PIN that lets you access your information from anywhere, which is handy should you ever lose your phone and need to wipe your card info. So far, it's amassed just over 2 million users who utilize the app to store an average of five cards' worth of info each.
Starting today, you'll see an option within the Smarter Wallet app to visit what Lemon is calling the Lemonade Stand, where you can browse a selection of third-party features that you can add directly to your Smarter Wallet. Third parties could include anyone from credit monitoring services to merchants and brands who want to push special offers or discounts at customers.
Lemon says it is also working to integrate Apple’s similar Passbook  app, so iOS6 users will be able to send their desired Lemon wallet cards to Passbook.
For merchants and brands, Lemon is also offering a new card maker tool called the SmartCard Wizard that will let them create custom tickets, coupons, and loyalty or gift cards without requiring coding knowledge. This helps Lemon market itself to merchant and brand partners as the go-to place to reach valued customers, eliminating the merchants' need for a separate, branded mobile app and instead running all their promotional offers within Lemon. That, in turn, helps Lemon sell itself as less of a digital backup for your wallet and more as a fully functioning merchant and commerce platform.
It's unclear if these add-ons will prove as valuable for the user. You have to explicitly grant third-party add-ons access to your Wallet, but once you do, the additional offers come through via (often dreaded) push notifications. That may come in handy for some add-ons, such as a price comparison tool, but Lemon's example , a reviews aggregator that prompts Lemon users to complete reviews for merchants they've visited, might get tiresome.
[Image: Flickr user Jack Fussell ]