Maximum effective ISO is an estimate of the highest sensitivity at which a camera can capture excellent quality photos.
Cameras with higher effective ISO will be better choices for indoor photography, night shooting, and indoor sports photography, especially if you intend to make large prints.
You can learn more at our glossary entry.
Maximum effective ISO test data courtesy of DxO Mark.QX1 test data on DxO Mark GM5 test data on DxO Mark
Cameras with longer battery life can take more photos before exhausting their batteries.
Special note: The measurement standard for battery life stipulates that if a camera has an internal flash, it must be used for 50% of photos taken. For this reason, comparisons of one camera with an internal flash to another without will not be comparable
Great image quality for a tiny camera; Excellent high ISO for its class; Built-in EVF; Built-in hot-shoe; Improved ergonomics; Improved image quality for long exposures; Improved burst rate with hybrid shutter; 1080/60p video.
Slightly bigger than GM1 (but not by much); No built-in flash; Shallow buffers with RAW files; Dynamic range not quite as good as some competing models; Below average battery life.