This approach is not maintained anymore by me, as I switched to a new tool, which I posted about here.
For my recent activies in calorie counting I used an excellent app called fddbextender which works with the large database of fddb.info. Unfortunately there are no statistics and graphs in the free version. If you’re a paying customer, the app offers some graphs, but I guess it’s only on a weekly basis. However it is possible to get a csv export from the website which contains every entry in the last 90 days.
I designed a small python script which connects to the website, logs in (with the credentials provided), and retrieves the fddb.info export. The data is aggregated to a daily level and then imported to a Postgres database. This can easily be run as a scheduled / cron job to update the database each day. The data then can be visualized with Grafana. It’s also fairly easy to calculate averages / min / max on a custom timeframe.
The only prerequisites are a running Postgres database (can be a different dbms, just edit the Python script) and the access token which can be obtained by analyzing requests when logging in to fddb.info.
For further information have a look at my Github and the readme of the repository, or get my prebuilt Docker image from Dockerhub.