Blixt Wallet Grant Application

Background

In the aftermath of the great blocksize war, the Lightning Network has sprung up as a feasible scaling solution for the Bitcoin Network. Over the years we have seen tremendous progress and adoption with lots of projects, innovations, ideas that make the network more robust.

There has been great progress in making Lightning easier to use, with concept of a Lightning Service Providers guiding the user regarding things such as channel management.

We have also seen protocols making Lightning Network wallets more interoperable with the web, with the web protocol suite LNURL along with the Lightning Address format, WebLN and other technologies.

Enter Blixt Wallet

Blixt Wallet is an open-source and non-custodial Bitcoin Lightning Wallet for Android, iOS and macOS.
It's a full Lightning node running a real vanilla lnd node inside the mobile app, giving tremendous power, utility and flexibility for the user. It uses Neutrino SPV when syncing the chain, which preserves privacy.

Users enjoy a convenient default configuration, but rather than abstracting away concepts such as channels, Blixt Wallet tries to present them in a pedagogical way. Funds sent to the wallet (on-chain or Lightning) will make use of the Blixt Lightning Service Provider called Dunder. This means it's easy for new users to get on-boarded to the Lightning Network.

For users who want more control, Blixt Wallet is designed to be customizable and they can enjoy a rich set of options. They can choose to sync with their own Bitcoin node and also stay more private by enabling Tor in the settings. If they have their own Lightning routing node, they can open a channel towards it instead of our Lightning node.

The Blixt Wallet project has an official Lightning node that wallet users can open channels to (with Dunder). The node is well connected within the network and usually ranks high on node scoring lists. This makes sure that users will have a good experience while using the wallet.

We keep up with cutting edge development and the app has very rich support for emerging technologies such as LNURL, Lightning Address, WebLN, Keysend and more.

Blixt Wallet stays close to lnd and the wallet is running it internally without any modifications. This means that Blixt Wallet funds can easily be recovered via lnd on desktop. Because of this design choice, Blixt Wallet is usually the go-to solution for users with an Umbrel node that has stopped working. They can safely recover their funds by restoring them with Blixt Wallet.

Blixt Wallet also has a lot of unique features that makes it stick out, such as a Contact List for LNURL-pay, LNURL-withdraw and Lightning Address codes. This will be further extended to support Keysend, BOLT12 and other emerging technologies.
We have also created bLIP-0011 NameDesc, which is a simple protocol to standardize recipient naming conventions in BOLT-11 invoices.
Blixt Wallet is one of the few wallets that has Keysend support, letting users send payments to supported nodes and services without an invoice.

On Blixt Wallet for Android, users can enjoy Lightning Address support via our Lightning Box service. We have taken a different approach to other self-custodial wallets in the space. Instead of using hodl invoices, Blixt Wallet will always remain active in the background in order to respond to incoming payment requests.

Strong Community

Active Android users

Despite being one of the smaller wallet projects, Blixt Wallet has a strong and helpful community. Users in need of help have a lot of guides and resources at their disposal.
The official Telegram chat group is very active with over 500 users. This is comparable to other more popular Lightning wallets. We have a healthy set of enthusiastic users and contributors that help out with suggestions, testing the app and more.

Ever since mid 2021, Blixt Wallet is seeing a steady growth in number of users. The app is spreading via grassroots support and we see independent people reviewing and posting about Blixt Wallet on YouTube, Twitter and other platforms.
Blixt Wallet is especially growing in Spanish-speaking countries, with an estimated 50% of users being Spanish-speaking. Since version 0.6.0, the app has been translated into Spanish (along with 8 other languages).

We have a rich knowledge base for our users, with guides, FAQ and other articles on our website as well as DarthCoin's Substack. User documentation is very important to us and we update it periodically.

A Bitcoin ethos midset

Blixt Wallet is being developed with a Bitcoin ethos. The wallet is fully open-source with an MIT license.
All related services and projects such as Dunder LSP and Lightning Box are also open-source and users can choose to run their own LSP if they want to.

We stay committed to Bitcoin and focus solely on improving the Bitcoin and Lightning Network ecosystem. The wallet only supports Bitcoin and we envision a world where Bitcoin would serve as the global, open and censorship-resistant currency.

Planning for the future

The Blixt Wallet project has many plans moving forward and we will list the larger topics here.

New app design

We intend to do a major overhaul of the app design and user-experience, integrating Dunder LSP, Lightning Address (Lightning Box) and possibly Nostr from the ground up.

Dunder LSP

Dunder LSP is our Lightning Service Provider software.
It's built in NodeJS and works together with a normal lnd node. This makes it easy for anyone to run their own LSP if they want to.

Dunder LSP currently uses its own API, but we intend rework both our Dunder server and Blixt Wallet app to support the LSP spec, which would make it compatible with other wallets and LSPs in the ecosystem.

We also wish to further extend the LSP software with other functionality such as LN<->on-chain swaps and other features.

Desktop versions

Blixt Wallet for macOS

Since version 0.6.0, Blixt Wallet is also available on macOS, joining as one of the few Lightning wallets for the desktop.

We are currently working on Linux and Windows versions too.

Chain side-loading sync optimization

Blixt Wallet currently uses a neutrino SPV client in order to sync headers and compact filters from the P2P network. As it can take some time syncing from the P2P network, we intend to add side-loading functionality to Blixt Wallet, in order to retrieve the data from an HTTP server instead. This would significantly speed up sync times.

PayJoin

Privacy is a very important in order for Bitcoin to succeed as global censorship-resistant money. We will work on implementing serverless PayJoin support to Blixt Wallet.

Miscellaneous features

In order to improve Lightning privacy and performance, we will work on supporting upcoming features such as BOLT12, blinded paths and stuckless payments as they come available to the ecosystem.