A simple todo mobile application and server for self-hosting and synchronization.

Instead of VTODO, a custom protocol is used to store and manipulate the data.

A single json file is used to store the task data. Below is an example of a task collection named my-daily-groceries containing a single task that recurs every 7 days.

my-daily-groceries.json

{
  "lastModified": 1711149159,
  "tasks": [
    {
      "id": 0,
      "title": "Buy Bread",
      "description": "Buy some bread while grocery shopping. Preferably something sourdough or baguette.",
      "location": "Best Bread Bakery, Vaughan, ON A1A 1A1",
      "category": "Grocery",
      "dueDate": 1711149159,
      "recurrence": [
        {
          "recurrenceRange": "noEnd",
          "interval": 10080,
          "endDate": 1713136359
        }
      ],
      "completed": false
    }
  ]
}

Each collection has a single dateModified parameter. This parameter is used to keep track of the latest task collection on each device.

When the mobile app updates a task collection, it will decide to overwrite the local task collection file based on the dateModified parameter of the remote task collection. If the lastModified value of the remote server's task collection is earlier than the local task collection, the local task collection will be pushed to the remote server. Otherwise, it will update the local task collection with the remote server's task collection.

Simple Tasks comes with a self-hostable server. Once configured, it will store all task collections. The application is written with Flask, so it needs a production server to run in a stable environment. Gunicorn can be used.

$ pip3 install gunicorn

Then, start the server on the desired port.

$ gunicorn -b 0.0.0.0:443 app:app

Once the server is up, add the server in the application. Each added server has its own password that is used in a Basic Authentication header.

img here showing a server being added in the android app

In the app folder you will find the project to build app. The APK will be added as a release as well.