I use the the Bearable app to journal my symptoms, energy levels, sleep, medications and more. This has helped me to see progress over time and determine which interventions are helping.
There's a bit of a learning curve, but after a couple days it becomes quite easy to do.
The real value is tracking things over time. Looking back at the last year, I can see clear progress in certain areas -- and setbacks in others.
You can customize the app quite a bit. If it seems overwhelming, you can customize the home page to display fewer points of data. Heck, you could even use it just to track mood and energy in just a few seconds each day.
You can optionally automatically sync health metrics from your smartphone, watch or other wearable device.