One problem when working with coins that are out of ICO is that it’s difficult to stay motivated and developing for very little reward or investing time and money without any kind of support from the community. TLDR; that’s what happened to the Worldcoin HD wallet.
In 2013 we released the first full Worldcoin wallet on Google’s Play store. It was based off the very popular Bitcoin android wallet by Andreas Schildbach and associates, with the Scrypt hashing code reused from another Scrypt wallet. This was a major step forward for Worldcoin because there were few cryptocoin developers with Android experience at the time.
The app worked very well and we had very few problems with it. Meanwhile the Bitcoin wallet received important updates to security and features, including things like highly-deterministic addresses, support for multi-signature and pay-to-script-hash transactions and the serious denial-of-service bugs from versions previous to 0.8.3. This all sounded like great ways to improve Worldcoin so a new wallet version was made that included all the updates and more. Sadly because of an incompatibility between Java’s and Android’s keystore tools, the old wallet couldn’t be updated directly. A new app was created instead called Worldcoin HD and the old wallet was labelled obsolete in the store.
The HD wallet had features that were not even officially supported by the Worldcoin Core yet. so we also updated Worldcoin Core to 0.10+ with all the DOS issues fixed, but that was never officially released. While we were working on getting support for an official Core release, we discovered that new seed nodes lists were needed in all wallets and that a net split had gone unnoticed for a while. Updating the seed nodes should have been trivial but we discovered that the 0.10 Core wallet would no longer validate the whole blockchain after fork was resolved.
Someone had used the net split to poison the blockchain with some of those DOS issues that were going to be fixed in the 0.10 Core. Since only one pool was using the 0.10 Core with the stricter validation code, these DOS-causing transactions had made it through for weeks after the code update was available. For example one bad block has so many tx-out that even with a large amount of RAM and a SDD, the 0.10 Core takes forever to validate. The old Worldcoin Core just ignores the problem and muddles on through.
With no one asking for the 0.10 update and a fork that couldn’t be rolled back, all work on 0.10 and HD wallets was simply abandoned. The Worldcoin HD code probably still works and Core could be upgraded to 0.10+ with enough miner support in the future but we haven’t done any of the work or expenses necessary to even keep the app listed on the Play store. If anyone would like to simply add new seed nodes and upload the code to a new app entry on the Play store, the code is still available on the.Worldcoin github.
I think it’s safe to say that the real value of a cryptocoin isn’t in the technology or the economic wizardry, but in how strong a community can be built around it.