Machankura v2.0 to Turn Feature Phones Into Bitcoin Signing Devices

"The next stage for Machankura, which is currently only a custodial Lighting solution, is enabling Africans to hold their own private keys, bringing them true financial self-sovereignty," reports CoinDesk.

Machankura v2.0 to Turn Feature Phones Into Bitcoin Signing Devices
  • Machankura's developer Kgothatso Ngako announced Machankura’s Bitcoin Java Card project at Adopting Bitcoin Cape Town conference. The project will let feature phones double as non-custodial Bitcoin wallets.
"Java Card is software that allows applets, basic computer programs that perform specific tasks, to run on smart cards, which communicate with the SIM cards in the phones. In this case, the Java Card software will enable African users to hold their bitcoin private keys, sign transactions and see their UTXO balance."
  • "The Java Card project is a chip that runs on your SIM card. You stick it on a normal SIM card [and] it adds the functionality you programmed on this chip on top of the feature phone. With this chip, you can then program an applet, which has Bitcoin-related functionalities like signing," was stated in the article.
"We have programmed the ability for it to produce a SegWit address [and] are now just waiting for the next part to complete where you are able to communicate with a relay, something like an Electrum server, where the server feeds you all the blockchain data and then you can [see] your balance," said the developer.
  • "Now, we can send a message to a relay from the Java card applet, and what we need to do is successfully receive a message via the Java Card project. The SIM card can receive SMS [with] the chip, but the chip cannot trigger events while it's on the SIM card. That is the part we are [still working on]," he added.

Learn more about the inner workings of the Java Card project in the following videos below.

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