This document discusses prioritizing which devices to test mobile apps on based on user reviews. It analyzes reviews from 99 Android game apps and finds that, on average, 33% of devices account for 80% of reviews. Some devices, like the Motorola Droid X, tend to leave more negative reviews due to performance issues. The document proposes using the percentage of reviews from each device to predict the top devices to test on. When applied to 98 apps, the top 10 predicted devices matched the actual top 10 devices 7 out of 10 times on average. This approach could help app developers focus their testing efforts on the most important devices.