Defying Internet Censorship with Offline Apps

We're witnessing an unprecedented surge in internet censorship worldwide. 

Last year, 296 government-induced internet shutdowns swept across 54 countries. From election-related shutdowns in India to protest blackouts in Hong Kong and military crackdowns in Russia, governments are increasingly weaponizing connectivity as a tool of control.

Thankfully, there is also momentum building around protocols that can defend against these crackdowns. By using Bluetooth mesh networks and cryptographic innovations, developers behind projects like Offline Protocol, Cashu, and BitChat are building the infrastructure for uncensorable communication and payments — no internet required. 

Let’s look at some of the applications recently gaining steam. 👇

🔌 Offline Protocol

Infrastructure layer Offline Protocol functions as a comprehensive toolkit transforming  smartphones into nodes of a decentralized network, enabling chat, file sharing, and crypto payments without any internet connection.

How it Works

The protocol works by leveraging built-in phone features like Bluetooth and Wi-Fi Direct to form mesh networks where each device acts as both a user and a relay point, meaning everyone routes messages for the entire network. Furthermore, the network is “self-healing,” so if one device goes offline or moves out of range, the network dynamically finds a new route for sending a message through other nearby devices.

This peer-to-peer system means the protocol operates without a central server, defending it against shutdowns and censorship.

• Current Features — The protocol’s flagship apps, OfflineID and Fernweh, showcase the network’s ability to support offline messaging for one-to-one conversations, group chats, and broadcasting alerts to nearby nodes — useful in protests, emergencies, or crowded events.
• Coming Soon: Next up for release are Offline Apps, think custom peer-to-peer applications running on the protocol, and Offline Payments, a toolkit for enabling full peer-to-peer crypto transfers.

After announcing a funding raise of $1.1M back in March, Offline recently integrated into the Binance wallet, allowing users to claim OfflineIDs directly through the wallet. There is currently a points system active (perhaps hinting at a future airdrop). 

🥜 Cashu

Next we have Cashu, an ecash protocol on Bitcoin built by privacy advocate Calle and enabling truly private, offline-capable transactions. 

How it Works

At its core, Cashu uses “mints” — trusted entities that issue tokens backed by Bitcoin. When you deposit Bitcoin into a mint, you receive ecash tokens that function as digital bearer assets: whoever holds them owns them, just like physical cash. There’s no account, no balance tied to your name — just tokens stored on your device. Mints don’t track users or transaction histories, making the system both censorship-resistant and resilient to surveillance or data leaks.

You can think of it like this: five people each give $20 to a blindfolded cashier, who puts all $100 in a vault. In return, each person gets a stamped paper voucher. Later, anyone holding one of those vouchers can come back and redeem it for $20. The cashier can only tell if the stamp is valid — they can’t see who originally handed over the cash or who receives the voucher. That’s how Cashu preserves privacy.

In the protocol, this “blindfold” is a mechanism known as the Blind Diffie-Hellman Key Exchange. The result is that even the mint can’t link your deposit to the tokens you receive or later spend.

• Offline Transfer Mechanics: Send tokens via QR code, Bluetooth, or even printed paper. The sender locks tokens to the recipient’s public key (a digital address), and the recipient redeems them when back online.
• Lightning Network Integration: Fast, secure Bitcoin transfers between mints are routed through the Lightning Network, providing seamless on/off-ramps while maintaining privacy.
• Programmable Conditions: Transfers can include rules like “pay only if X,” enabling conditional payments without complex infrastructure.
• Open Source and Modular: Anyone can run a mint — for wallets, paywalls, content access, reward systems, or anything else. Cashu is free, open-source, and designed for easy integration.

Cashu v2 has solidified the full offline flow: deposit Bitcoin, receive ecash, transfer tokens peer-to-peer through any medium (QR code, Bluetooth, etc.), and redeem them once reconnected. A major milestone for the protocol came recently with its integration into Jack Dorsey’s BitChat (more below), which now supports a native Cashu wallet.

Beyond BitChat, Cashu’s developer ecosystem also proves quite robust, with a growing suite of libraries that make it easy to build new wallets and mints. Multiple open-source apps already implement the protocol and can be explored here. 

There is one clear catch to Cashu — in its current iteration, the protocol must rely on trusting mint operators who hold the underlying Bitcoin. Given this custodied nature, there is the risk of these operators issuing unbacked ecash or rug-pulling users without safeguards. There are ongoing efforts to solve this though with cryptographic systems like specialized Merkle Trees and STARKs to enhance trustlessness and transparency.

💬 Bitchat

Recently launched by Jack Dorsey, Bitchat transforms phones into a relay network for messages — using Bluetooth to hop data from device to device with no internet required. 

How it Works

Similar to Offline Protocol, Bitchat operates through mesh networking, allowing messages to "hop" across phones up to 300 meters, with each device relaying for others like runners passing a baton. This creates a decentralized communication fabric that can't be shut down by cutting internet cables or blocking servers. The encryption stack implements a series of different cryptographic methods to ensure that even if authorities capture devices, past messages remain unreadable.

• Complete Anonymity — No phone numbers, no accounts, no identity verification — users exist only as cryptographic keys, making surveillance nearly impossible 
• Panic Mode Security — Triple-tap to instantly erase all data, while dummy messages hide communication patterns from traffic analysis
• iOS and Android Support — Bitchat supports both iOS and Android devices, already live in the Apple App Store, though one must install it via the source code for Android.

While Bitchat has attracted over 10K beta testers and generated strong interest through viral Cashu-enabled ecash transfer demos, it remains early. 

The protocol has not yet been battle-tested at scale and, while recent updates have improved Bluetooth handshakes and connection stability, real-world reliability still comes limited by sparse user density — in many areas, setting it up may reveal no nearby peers. To be fair though, the app was only officially released a week ago. Given its open-source nature, I imagine it’ll invite a strong global developer community soon, especially given its continued interplay with Cashu.

Overall, these protocols represent unique approaches to furthering crypto's core value proposition: maintaining sovereignty when traditional networks fail or become weapons of control.

Growing shutdowns make the case clear  — internet blackouts have become a standard government response to dissent. What started as edge cases in authoritarian regimes has evolved into a global playbook even in “civil” societies.

While early or still in development, Offline Protocol, Cashu, and Bitchat exemplify clear action being taken by a crypto (and Bitcoin, if we’re splitting hairs) base to further create parallel infrastructure that protects connectivity in an increasingly hostile world, the same way Bitcoin protects value in an increasingly inflated world.

As shutdowns grow more sophisticated, from surgical app blocks to complete blackouts, the need for proximity-based, cryptographically-secured alternatives will continue to move from theoretical to essential tooling.