I agree with ville. Set up same configuration build: 1469410939, app: 29. I used two meters and two android phones, both android 5. Android displays set to never turn off. Used two different brand of SD cards and in fact the same cards I have used in the meter in the past. Did not move the meters or the phones.
Started logging at 1s rate, metering page active. One app went back to scan page after 4 minutes and the other app after about an hour. Both meters blink changed to double blink every 10s.
Restarted one meter (4s meter) again same configuration. A few hours later when I checked, I found logging turned off. The SD card log shows it stopped logging after 1.5 hours.
I have restarted the other meter (the 1 hour one), but this time I set logging interval at 10s. It appears to still be logging after close to 4 hours.