Is Nexus 5 GSM or CDMA?

2300mAh

Network	Technology	GSM / CDMA / HSPA / LTE
	CDMA 800 / 1900 – North American version
3G bands	HSDPA 800 / 850 / 1700 / 1900 / 2100 / 900 – North American version
	HSDPA 850 / 900 / 1700 / 1900 / 2100
4G bands	1, 2, 4, 5, 17, 19, 25, 26, 41 – North America

When was the Nexus 5x released?

October 2015
Nexus 5X/Release Date