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A month ago, I released a new version for open testers on Testflight. After one week, I found that the number of installs was much lower than the previous version(10 vs 50+). So I check with our testers' latest version on their device. I count how many people updated the latest version by myself. The exact number was much higher than the number shown in the account (50 vs 10). Then I asked Apple support, he said one possible reason is the number of installs referenced is the number of new installs of the beta build. I searched the official definition of the number of installs, it means the number of installations on devices. And my previous version has very stable numbers except this new one. I am confused about this issue and what is the exact definition of the number of installs. I would appreciate it if someone can help me. Thanks!