Signal creator Moxie Marlinspike has announced MobileCoin, an ambitious project that purports to overcome the limitations that prevent bitcoin from serving as a viable medium for small-value payments.

It’s no secret that the user experience has largely taken a backseat to innovation in cryptocurrency development. While this was understandable during the technology’s early days, cryptocurrency’s rapid journey into the mainstream has necessitated the creation of a more accessible user experience so that, according to the common parlance, even your grandma can use it.

Unfortunately, improved accessibility has come primarily at the application level through third-party services that require users to sacrifice — to varying degrees — privacy, and security, and even control over their private keys.

MobileCoin revealed by Moxie Marlinspike

Released this week, the MobileCoin whitepaper (PDF) reveals a roadmap — still in its early stages — to make cryptocurrency usable for everyday transactions without sacrificing security and decentralization.

“I think usability is the biggest challenge with cryptocurrency today,” Marlinspike told Wired. “The innovations I want to see are ones that make cryptocurrency deployable in normal environments, without sacrificing the properties that distinguish cryptocurrency from existing payment mechanisms.”

Drawing on his experience developing end-to-end encrypted messaging systems at Open Whisper Systems, Marlinspike envisions a mobile-focused cryptocurrency protocol that will integrate seamlessly with secure messaging apps such as Signal and WhatsApp. Significantly, users will be able to recover their funds using a simple four-digit PIN code, eliminating the complexity of private key management.

MobileCoin will be based on the federated Stellar Consensus Protocol (SCP), enabling transactions to process in less than a second. While nodes will do the “heavy lifting” for the network by handling transaction processing, the whitepaper claims that they will not be able to “learn anything about their users’ balances or transaction history.”

This will be accomplished through a layered approach that isolates nodes in SGX secure enclaves and also employs CryptoNote — the same basic protocol on which privacy-centric Monero is based — to provide users with one-time addresses that cannot be linked together if node operators successfully compromise SGX.

At four pages, the MobileCoin whitepaper is incredibly brief, and security researchers have stated that many questions remain about the use of federated protocols and SGX enclaves — questions that the developers will hopefully answer in the coming months.

Nevertheless, given Marlinspike’s development chops, MobileCoin is a project worth keeping an eye on.