Signal, the rapidly growing chat app, is allowing its users to make payments with the cryptocurrency MobileCoin, the non-profit behind the app announced yesterday.

Some Signal users would be able to link their accounts to a MobileCoin wallet and send and receive cryptocurrency transactions within the app.

Both Signal and MobileCoin were developed in response to privacy incursions by existing chat apps, according to Wired. Development of Signal is led by WhatsApp co-founder Brian Acton and the noted cryptographer Moxie Marlinspike.

The Signal integration with MobileCoin will not allow the chat app to view a user’s balance, transaction history or have access to the funds held in the MobileCoin wallet. The feature will be available to Signal users in the U.K. but the trial will be expanded, according to a blog post from the app’s developer.

Signal doesn’t disclose the number of users it has, but it ranks at the top of Apple and Google’s app charts in dozens of countries, according to TechCrunch. Analysts at App Annie told TechCrunch they estimate Signal had about 20 million monthly active users in December, with the number of downloads growing in January.

The price of MobileCoin has surged in recent days. It was trading at about $7 at the end of March but it hit a high of $67 after the Signal announcement, a nearly ten-fold increase. MobileCoin went live in December.

Marlinspike serves as a technical adviser to MobileCoin while leading development of Signal. MobileCoin raised about $11 million in new funding from venture funds last month. 

Photo by Dimitri Karastelev via Unsplash