What is the difference between total installs and active installs in the Android market?

Question

What is the difference between total installs and active installs?

I have 90 total installs for my app and only 47 active installs. What does it mean?

Answer 1

The Active Install figure can be wrong. I just uploaded the app and installed it on my phone. The next day when I logged in to Android dev backend, I could see 1 Install and 0 Active Install.

I hadn't un-installed the app. This shows that the figure can be misleading.