I have been working on a few mobile applications for a while now and felt like I was always flying blind, not knowing how users would use the application and mostly not knowing if the applications crashed somehow.
For the web, I was using my instance of Matomo.
At first, I decided to go that route. It did not start well, as the Flutter client was using plugins. That seemed overkill for only posting events to a webserver when Dart has a good HTTP client. I ended up implementing a simple Dart client (https://pub.dev/packages/matomo/). It was suitable for a while, but web analytics is just not the same as mobile analytics.
Since I am trying to bootstrap a business, I am conscientious about which services I subscribe to. It can add up very quickly. I was, thus, looking for a cheap mobile analytics tool.
I am also conscientious about users privacy and trying to stay away from the large companies offering "free" services.
Finally, I prefer to write mobile applications in Flutter to be on both Android and iOS easily.
In summary, I was not happy with what was out there, and as an engineer, I tend to prefer building things myself.
As you might have guessed, I ended up writing a custom solution. It started as a simple library and minimalist backend, and then I decided I'd share it with the world by making it open-source.
After a few weeks of extra work, I'm announcing femtolytics, a lightweight open-source mobile analytics solution.
So far, I've only written a client library for Flutter applications in Dart (https://pub.dev/packages/femtolytics).
The protocol (https://github.com/femtolytics/django-femtolytics/blob/master/PROTOCOL.md) is straightforward, so anybody could write a Swift, Java, or Kotlin client if I don't get to it.
The backend is a Django application (https://github.com/femtolytics/django-femtolytics).
There is a sample Django project (https://github.com/femtolytics/django-femtolytics-sample) that shows how to integrate it with your project. With minimal effort, you can probably deploy it on your server.
I'm also offering a hosted solution at https://femtolytics.com.
I am keeping it cheap for unlimited usage at the moment. I'm also offering a discount for the Indie Hackers community. User Coupon Code Q51BFMGO when subscribing ($10 off for the first year, for the first 25 people)