iBayanihan

The Problem

During natural disasters in the Philippines, cellular and internet infrastructure often goes down for days. Affected communities lose their primary communication channel when they need it most — for coordinating evacuations, requesting aid, and checking on family.

The Solution

I built iBayanihan as a mesh messaging platform that works without internet via Wi-Fi Direct peer-to-peer connections.

• Wi-Fi Direct mesh — Devices form ad-hoc networks, relaying messages across multiple hops to extend range beyond direct Wi-Fi reach.
• End-to-end encryption — All messages encrypted locally before transmission. Even relay nodes cannot read message content.
• Group and individual chats — Standard messaging features that work entirely offline.
• "Hubs" — Dedicated channels for LGU (local government) and business communications with announcements, FAQs, and offline chatbot-based support for common disaster queries.
• Online sync — When internet returns, messages sync to Supabase for backup and cross-network delivery.

What Went Wrong

Wi-Fi Direct device discovery was unreliable on certain Android versions — some devices would intermittently fail to find nearby peers, fragmenting the mesh network.

The fix: I implemented a hybrid discovery mechanism that combines Wi-Fi Direct service discovery with periodic broadcast beacons. Devices that fail passive discovery fall back to active scanning, and the mesh routing table is shared between connected peers so new devices can bootstrap from any existing mesh member.

Results

• Internet-free communication via Wi-Fi Direct mesh networking
• End-to-end encryption for all messages
• LGU "Hubs" for official disaster communication and offline FAQ bots