Payment processor Braintree announced a new set of tools for mobile app developers. What makes the tools interesting is that they let e-commerce, or m-commerce to be precise, merchants accept payments within a mobile app instead of having the app launch a Web browser to process the payment, a standard (though not always obvious) practice.

The company said it expects interest to be strong from developers.

"Braintree handles a tremendous amount of mobile payments volume today, and these new client libraries solve a problem for mobile app developers who want to provide the simplest and most elegant purchasing experience for the customer, instead of using a Web browser simulated to look like the app," said Braintree CEO Bill Ready.

Additionally, the new tools from Braintree help developers avoid PCI-compliance issues, the company said. It does so by encrypting payment credentials when the user enters them on the mobile device. It then passes only encrypted data from the merchant's server to Braintree for decryption and processing; thus no data is ever stored on the merchant's server. No credit card data stored on a server means it's technically out of scope for PCI.

The company said it's already processing more than $4 billion in credit card volume per year and is adding more than 100 new clients a month. Its current roster of clients includes LivingSocial, Airbnb and Shopify.

Last year the Braintree secured $34 million in Series A funding from Accel Partners.

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