flop

Is a WebRTC chat client for KaiOS, built with a local-first approach — your data stays on your device by default. Currently, you can exchange text messages, pictures, and your location with others. You can create new chats and join existing ones.

Features

• join chat
• share location
• share live location
• share image
• audio message

yes, but

In order to establish a connection between 2 peers, you have to know the id of the peers. To do this, I use the API: mozActivity / webActivity, which enables the exchange via a URL (sharing by SMS or EMAIL).

How to install

• KaiOS Store
• Sideloading step-by-step article by martinkaptein

Test Version

https://flop.chat/

Data objects

User profile

settings.unique_id

• Generated once during installation of the app.
• Serves as a persistent, internal user ID.
• Used for internal logic.
• Cannot be changed via the user interface.
• Typically generated as: flop-<uuid>.

settings.custom_peer_id

• Separately generated ID for identification on the PeerJS server.
• Used for signaling and establishing connections between peers.
• Can be changed by the user, e.g., to prevent spam through identifiable IDs.
• Typically generated as: flop-<uuid>.

nickname

• The nickname is a human-readable identifier for the user.
• It is used to generate the user's profile icon, ensuring a visually identifiable representation.
• The nickname has no security relevance and is not required to be unique.
• It is typically auto-generated (e.g., a random string) and can be changed by the user to personalize their appearance in the app.

Initial data object

{
  nickname: generateRandomString(10),
  custom_peer_id: “flop-” + uuidv4(16),
  unique_id: “flop-” + uuidv4(16)
}`

These objects are sent and received; they always have the same structure, only the payload object differs depending on the type.

{
nickname: string,
type: string, // "text", "image", "audio", "gps","gps_live","pod","ping","typing"
payload: object, // varies by message type
id: string, // uuidv4()
datetime: Date,
from?: string, // only stored locally in chat_data
to?: string, // only stored locally in chat_data
pod?: boolean // only stored locally in chat_data (always false)
}

ping

fires a silent data packet at regular intervals to update the connection status, Mainly used for KaiOS2.

{
  nickname: string,
  type: "ping",
  payload: {},
  from: string,
  to: string,
  id: string
}

pod

Proof of delivery
A silent message is sent back when a data packet has arrived.

{
  nickname: string,
  type: "pod",
  payload: {},
  from: string,
  to: string,
  id: string
}

typing

when the user is currently writing

{
  nickname: string,
  type: "typing",
  payload: {},
  from: string,
  to: string,
  id: string
}

text

{
  nickname: string,
  payload: { text: string },
  datetime: Date,
  type: "text",
  from: string,
  to: string,
  id: string,
  pod: false
}

image

An image is sent as base64 and stored as blob

{
  nickname: string,
  type: "image",
  payload: {
    image: string,
    filename: string,
    mimeType: string
  },
  id: string,
  datetime: Date
  pod: false

}

audio

an audion is sent as a arrayBuffer and stored as blob

{
  nickname: string,
  datetime: Date,
  type: "audio",
  payload: {
    audio: Blob,
    filename: string,     // "<id>.mp3"
    mimeType: string
  },
  from: string,
  to: string,
  id: string,
  pod: false
}

gps_live

The current geolocation of the device is sent, and the message is updated at the recipient's end.

{
  nickname: string,
  datetime: Date,
  type: "gps_live",
  payload: {
    lat: number,
    lng: number
  },
  from: string,
  to: string,
  id: string,
  pod: false
}

gps

The current geolocation of the device is sent

{
  nickname: string,
  type: "gps",
  payload: {
    lat: "",
    lng: ""
  },
  id: string,
  datetime: Date
  pod: false

}

Build your own

Installing the dependencies
npm -i

Build KaiOS 3 app
npm run build

Build KaiOS 2 app
npm run build-k2

If you want to create a browser version
npm run web

TURN-SERVER

To establish a connection, a TURN SERVER is usually required. This server does not store any chat data but only forwards it. The default server used is https://www.metered.ca/tools/openrelay/, which offers a free plan and is very reliable. The access data should be stored in an .env file.

TURN_APP_KEY=xx TURN_APP_NAME=xx

https://www.metered.ca/tools/openrelay/

LICENSES

• peerJS MIT License
• mithril
• leaflet
• dayJS
• openstreetmap

Donation

If you use the app often, please donate an amount to me.