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The Nexus 5X is a joint effort between LG and Google. LG made the hardware, and left the software to Google. It's the smaller, more affordable Nexus phone from 2015. For the price it has some competitive hardware, and it will be first in line for future software updates like Android N which expected to launch in the fall.
Specs
Pros
Pro Acceptable battery life
The battery isn't enormous at 2700mAh, but it should last a full day on all but the longest, most heavy-use days.
A looped 90 minute video at 100% brightness drained the battery by 32% which is a poor result. If the screen is on constantly, battery will drain fairly quick. In standby, the Nexus 5X barely uses any power. While most other phones will use up 10% throughout the day in idle mode, the Nexus 5X will use significantly less power thanks the the Doze feature which puts the phone into a deeper sleep.
GSMarena rates the 5X at 60h, which is enough to last a full day with regular usage.