Would be good if users could choose to have the lock button default the device into deep sleep mode to conserve battery. My new from factory play date with firmware 2.7.3 on a full charge last no more than 24 hours in sleep mode, with one hour of play in between, before requiring recharging (with wifi set to "ask"). Until the battery issues are resolved the option to have the lock default to deep sleep would make this device a little bit easier to carry around and use.