BillGuard is announcing Monday that it’s integrating with mobile wallet app Lemon, which means that Lemon’s 2.5 million users will be able to check their card balances and look for suspicious charges through their Lemon app. That follows a previous integration in September with Apple’s Passbook, which similarly enabled people to monitor credit and debit card transactions through Passbook.

Lemon users on iOS and Android who upgrade to the latest version of the app will now be able to see their balance and a list of recent transactions on stored cards in Lemon’s wallet, alongside their other cards, coupons and receipts. BillGuard builds a crowd-sourced database of billing complaint information to protect against fraudulent or hidden charges. Users help BillGuard get smarter by sharing their transaction information and get alerts on questionable activity. Since launching in last year, BillGuard, which hasn’t released user numbers, said it has saved its users more than $1 million.

The integrations with Passbook and Lemon are big opportunities for BillGuard to expand its mobile presence and pull in a lot more data from mobile users. Passbook lets BillGuard reach a lot of iPhone users and now with Lemon, which is not tied to one platform, BillGuard can reach tons of Android users as well. BillGuard plans a mobile app later this year.

BillGuard support provides a nice boost to wallet apps like Passbook and Lemon, showing how they can be a daily tool for consumers. Users are still figuring out the value of a mobile wallet, which many people think of in the context of payments. As Passbook and Lemon demonstrate, there’s a lot of opportunity in replicating the other parts of a wallet, including storing identity and loyalty cards to presenting receipts, tickets and coupons. BillGuard can also help consumers prepare for a mobile wallet future, giving them some assurance that they have more tools to keep track of all of their transactions.

BillGuard started out as a consumer-facing service but it’s now also courting banks, which will offer BillGuard services to customers. Yaron Samid, BillGuard’s CEO and founder told me the company is close to announcing its first big banking customer soon. The company has raised $13 million to date from Khosla Ventures, Peter Thiel’s Founders Fund, Eric Schmidt’s Innovation Endeavors, Bessemer Venture Partners and IA Ventures.

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On Wednesday Lemon is introducing Lemonade, a platform that lets publishers connect to Lemon through a new API. Previously, users had to take a picture of cards, coupons and receipts they wanted to store in the Lemon app. On a basic level, Lemonade will let companies connect their payment, membership and gift cards, coupons and tickets right into the Lemon app and will allow them to communicate with their consumers through the app. Lemon is offering a SmartCard Wizard, to help publishers easily build their own cards inside Lemon.

Lemon also wants developers to create add-on services that can provide additional value on top of the Lemon platform. Users will be able to browse a list of add-on services that offer discounts, offers and other services that interact with the data users store on their Lemon app. To help encourage development, Lemon is offering a $20,000 challenge for developers who create the best add-ons. There’s also a data dashboard for developers to see anonymous data on users, including demographics, spending habits and redemption rates for offers.

Opening up to third-party publishers will pit Lemon against Passbook and perhaps Google’s larger vision for Google Wallet. Lemon founder and CEO Wences Casares told me Lemon will integrate with Passbook so users can send some cards over to Passbook.

But he believes Lemon will be a broader and more flexible tool for users, allowing them to not just call up information but manage their cards and communicate directly with providers through the app. He said publishers will be able to sell services through the app. For example, a credit card company could enable users to sign up for another card through the Lemon app. And unlike Passbook or Google Wallet, Lemon is available on Android, iOS and Windows Phone devices.

Lemon has more than 2 million users of its app, which is nice but much smaller than Apple’s addressable market with Passbook, which is in the hundreds of millions. It will be tough to convince some brands and publishers to connect to Lemon without a larger audience to justify the investment. But it shows how mobile wallet apps don’t have to be solely about payments. There is still a lot of room to compete to be an organizer of all the other stuff that goes into people’s wallets and purses.

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The new money will help Lemon tackle what it calls its Smarter Wallet platform, which uses a broad definition of a mobile wallet. Oftentimes, we think of mobile wallets as just payment tools, but a wallet is really a place where we store a lot of cards, receipts, coupons and other items. Lemon’s Smarter Wallet will allow people to take a picture of all their payment cards, drivers license, loyalty and healthcare cards, as well as receipts, tickets and coupons. Initially, these will only be images that create a back-up wallet of sorts so users can’t really pay with their card or tap their phone to get loyalty points. The idea for now is to give people one place to hold on to all of the information they store in their wallet.

The app is secured with a 4-digit PIN, but also uses a 32-bit encrypted system to keep the stored data safe. Lemon applies the same optical character recognition technology it uses on receipts to understand the card information, so it knows how to organize the data. Ultimately, the goal is to make the wallet even more powerful by allowing users to track their spending on their various credit and debit cards, see their loyalty point balances or get alerts on their card expirations. And later, the different compartments in the wallet, such as spending and loyalty, will be be allowed to talk to each other, so potentially a user can get loyalty points based on their credit card spending without having to carry their loyalty card.

Even with its more modest initial steps, Lemon can still be helpful in the event a user loses their wallet. I can imagine using this just to enter in my credit card info on online commerce sites, when my wallet is in the other room. But ultimately, Wences Casares, Lemon’s co-founder, believes that a wallet such as Lemon will be a key application sitting on the home screen of everyone’s phone. He said the goal isn’t necessarily to handle check-outs, because paying by phone won’t be very convenient for years.

“We thing it’s more likely that users will want to go to one place but where everything is aggregated for them,” Cesares said.

Lemon, however, faces competition, most notably from Apple, which just announced a new iOS app called Passbook, which can store loyalty cards, concert tickets and airline boarding passes on a user’s mobile device. The app can work with a user’s lock screen and displays a barcode that can be used to complete payments or redeem awards.

As I wrote in February, Lemon is already evolving beyond its original roots to become more of a mobile Mint-like service. Users can now categorize, filter and total up spending, making Lemon more than just a repository for receipts. I think it makes sense for Lemon and Apple and others to aspire to build wallet apps. We have a lot of people concentrating on creating apps that make it easy for people to pay. But payment isn’t that broken right now and many next-gen mobile payment services will require a lot of work to become appealing to people compared to cards and cash. But I have a lot of cards, receipts and coupons in my wallet right now that make it much thicker than it has to be. Providing more ways to simplify that experience would be welcome for me and a lot of other consumers.

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Before the holidays, Apple put its foot down and delayed shipment on all new larger iMac orders until after Christmas. The ordering page for the 27-inch machine changed today to three weeks, extending delays further still. Maybe it’s just a backlog resulting from the initial delays, but reports of problems don’t seem to be slowing down, so that doesn’t seem likely.

Let’s review the storied past of the iMac that held so much promise when it was announced. Very shortly after that announcement, as soon as the first units started shipping, reports came in from users about problems with Flash performance, hard drive spindowns, bad Snow Leopard installs and permissions issues. So it tripped a bit out of the gate, but this is a distance race, not a sprint, right?

But as the race continues, the iMac in question doesn’t seem to be improving its performance. The display seemed to be the primary cause of concern as time went on. People reported cracked displays on delivery, screen flicker that drove a whopping number of customers crazy, and visual noise and dead pixel issues. The latest and most talked about complaint is significant screen yellowing and gradient change from top to bottom of displays on the 27-inch model.

The screen isn’t the only problem, though. Out of the box, some users are reporting DOA machines that just would not boot, and more complaints than any other about processor performance. A friend of mine had to return theirs twice for the same issue, and still hasn’t received a problem-free unit. Apple has tried software fixes, too, but they haven’t worked for everything.

The question isn’t really whether or not the 27-inch iMac is a lemon, it’s how Apple let this happen to begin with. Cupertino is not known for a tendency to rush machines into production before they’re ready, but this has all the earmarks of that exact situation.

Perhaps Apple was distracted by the tablet it’s apparently been developing, and if so, I’m not optimistic about the future of the Mac line. With the iPhone and a brand new similar platform in the tablet, will QA suffer in other areas? Apple’s reputation depends on two things: innovation and reliability. I, for one, am not willing to sacrifice one for the other. Are you?

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