ATM's work with debit cards and credit cards to give you quick, easy access to cash. There are over 400,000 of them across the United States and their popularity might explain why many banks and tech companies have been testing more convenient alternatives to the bank card standard.

Starting with an initial rollout in San Fransisco this month, Bank of America is giving its customers the option of withdrawing cash at Bank of America ATMs using their Android-powered phone. If you find yourself taking your phone everywhere but leaving your wallet at home a lot, this may come as welcome news.

In what can be called the features phase of the expanding war for mobile payments market share, Google has announced a flurry of upgrades to its Android Pay electronic wallet app that will surely broaden its appeal. The ATM deal with Bank of America is one of these.

The move towards providing consumers with real practical services like ATM cash withdrawal might help the digital wallet compete with Samsung Pay. Android Pay's main rival in the war for the tiny percentage of Android users who make use of mobile wallets struck a note with phone users by including compatibility for magnetic strip credit card readers.

Electronic wallets let you use smartphones and tablets to make money transactions by tapping funds from a credit card, debit card, bank account or prepaid account.

In the newest version of Android Pay, you'll be able to link your Bank of America debit card to the app, saunter up to a Bank of America cash machine, tap your PIN into the app and withdraw money from your bank account.

Initially, about 600 ATMs in the San Francisco area will receive this functionality, but that number should climb to 5,000 nationwide by the end of 2016.

If you are a Bank of America customer and want to test out this new gimmick, keep your eyes peeled for ATMs which display the contactless symbol. This looks something like a hand holding a card while being bombarded by radiowaves.

Admittedly accessing an ATM via a smartphone rather than with a debit card is probably no great gain in convenience. However, it may enhance security, as prying eyes won't be able to steal the debit card number. If you lose your electronic device, your wallet will be near useless for thieves because both your phone and Android Pay are protected by secure technology.

Android Pay is also unwrapping the ability to integrate loyalty card payments. It works this way: Say you walk into a Walgreen's store to do a little shopping, but don't have a Walgreen's loyalty card with you, either because you don't normally carry it around or you haven't signed up for one. Android Pay solves this problem by allowing you to tap a button in response to an email, push notification or SMS message to associate your account with your e-wallet.

If you need an account, Android Pay will pre-populate the Walgreen sign-up page and then link to the new account. Now, when you check out, you'll receive the benefit of Walgreen's loyalty program in the form of points and discounts.

This functionality will work with a number of different store loyalty programs, and follows closely on the heels of Samsung Pay, which added loyalty and gift card integration into its mobile wallet last week.

Behind the scenes, Google is increasing merchant software developers' access to Android Pay functionality by making publicly available the program interface to the app's Payment Request service.

This application programming interface, or API, includes a simple toolkit allowing developers to create a standardized payment experience for different platforms and browsers, which is considered vital for retaining customers.

For example, capabilities such as auto-filled checkout fields have led to a 25 percent increase in app use. Shopify and are among the first merchants adopting the new Android Pay API.

Access to the Android Pay Payment Request API will also allow mobile users to interact with certain apps before first installing them. That's because developers will be able to integrate the Android Pay platform into their own apps to provide single-tap, streaming transactions that mimic the look and feel of these apps.

Google has also added support for third-party payment processors such as Braintree, Vantiv and Stripe. For payment processors that don't currently support Android Pay, Google is debuting a self-service API that will allow integration.

Mobile electronic payments are gaining popularity with consumers, and Google is doing its bit to make Android Pay more functional and responsive to customer needs.

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