My source:
BatteryCare - Proper laptop battery usage guide
Fully discharging a Li-ion is not good.
I sit corrected.
"Full battery discharges (until laptop power shutdown, 0%) should be avoided, because this stresses the battery a lot and can even damage it. It's recommended to perform partial discharges to capacity levels of 20~30% and frequent charges, instead of performing a full discharging followed by a full charging."
Still I suggest you reboot your phone every once in a while as an app can be stuck in RAM.
I think it's going to be something that you will find conflicting everyday, for example:
"Allow partial discharges and avoid full ones (usually)
Unlike NiCad batteries, lithium-ion batteries do not have a charge memory. That means deep-discharge cycles are not required. In fact, it?s better for the battery to use partial-discharge cycles.
There is one exception. Battery experts suggest that after 30 charges, you should allow lithium-ion batteries to almost completely discharge. Continuous partial discharges create a condition called digital memory, decreasing the accuracy of the device?s power gauge. So let the battery discharge to the cut-off point and then recharge. The power gauge will be recalibrated."
Five tips for extending lithium-ion battery life | TechRepublic