While traveling in cruise ships, flights While camping in forests Natural disaster Inside schools or campuses where Internet is prohibited Internal events or closed group parties Civil protest
Here is a really good article on mesh networks, one of the primary tech deployed while developing offline messaging apps.
1. FireChat
FireChat is the most popular app when it comes to sending messages without the Internet or cellular data. In fact, it became widely popular in September 2014, in civil protestors in Hong Kong. One of the key reason for its popularity is the availability on both iPhone and Android. Depending on the iPhone model you have, The app’s developers claim the app can reach a distance of up to 200 feet. You keep on connecting more iPhones and the distance it covers will increase even further. Once an offline network is created, you can send offline private messages.
The more users, or devices, you have in your network, the wider your reach is and the more area it covers. FireChat achieves this feat by creating a mesh network using Bluetooth to connect and WiFi to create a P2P or peer-to-peer network. The cool thing about FireChat is that you can use it to also send photos and other files, and not just text messages. Useful for sharing snaps related to an event, for example. You can create a group of up to 50 people and also send 1-to-1 messages privately using an encrypted connection. Pros:
Send text, images, and files Range is 200 feet per device End-to-end encrypted private messaging Works on iOS and Android
Cons:
Group limit up to 50 people
Download FireChat: iOS | Android (Free) Also Read: iPhone Not Sending Text Messages? Here are 12 Ways to Fix It
2. Peer Chat
Peer Chat was born from the ashes of Air chat, another open source end-to-end encrypted messaging app that works offline. Peer Chat is devoid of all the flaws that came with the former. With a beautiful and functional UI, Peer Chat is a offline messaging app for iPhone that uses both Bluetooth and WiFi to send messages and files. Air Chat could only handle text messages but the developers have fixed those issues. You can also send emojis now!
On the flip side, the group size is limited to 8 at the moment which is not a lot, but still should do for a small group of friends or family. Peer Chat is open source which means it is also very secure and your data is never logged or saved anywhere. There is no support for creating a mesh network which means you can’t create an on-going network of users like in FireChat. More suitable for private, small group chats. Pros:
Open source Send text, images, files End-to-end encrypted No log policy
Cons:
Group limit up to 8 No mesh network support Works on only iOS devices
Download Peer Chat: iOS (Free) Also Read: How to Send Self-Destructing Messages on Slack
3. Bridgefy
Bridgefy is a popular Firechat alternative. As the name suggests, it creates an offline bridge using a mesh network. It works similarly to FireChat with some key differences. The distance it covers is up to 300 feet which is significantly more than any offline messaging apps.
Once installed on both phones, you need to sign up via your phone number for text verification. Next, the app will ask if it can make data available to nearby Bluetooth devices. Grant it this permission or the app will not work. It also comes with a broadcast mode where you can send emergency messages to anyone nearby or connected to the mesh network at once. Useful for situations like when you are in a sports stadium and want to make an announcement, or when there is some kind of emergency and you have no network connectivity. The app supports both text and image-based messags. Download Bridgefy: iOS | Android
4. Litechat
Litechat allows you to create multiple accounts using the same mobile number which is really cool. Useful when you want to stay truly anonymous. There is no way to share videos or other file types however you can send text messages to people around you.
Another neat feature is the 24 hour automated deletion which means all your messages will be deleted once the day is over. Be mindful that users can still take screenshots of your messages but still, worth a shot. Litechat also has a really good user interface which is colorful. Pros:
End-to-end encrypted Auto deletion of messages Create multiple accounts with same number
Cons:
Only text messages supported No mesh network
Download Litechat: iOS
5. Text nearBy
Text nearby only works by using your iPhone’s Bluetooth which means the range is significantly lower at 33 feet. Useful for classroom or household communication or when your friends are in the proximity. There are no servers and hence there are no logs either. It’s just you and your friends.
You will know your friends are nearby and ready to send and receive message when the plane icon turns green. Pros:
End-to-end encrypted
Cons:
Only text messages supported Range is only 33 feet No mesh network
Download Text nearBy: iOS
Offline Messaging Apps
These are some of the best messaging apps that work offline without an active Internet connection or even signal. All it needs is Bluetooth and LAN or mesh network. If you are looking for something to play with your kids in the house, Text nearBy is as good an app as any. If you are looking for a broadcast network to be used in case of emergencies, Bridgefy is a really solid app. For everyone else, I would recommend FireChat. Both FireChat and Bridgefy support creation of mesh networks which really increases their utility
