On 17 October 2014, two days after announcing Lollipop, Google published the
final Android 5.0 SDK and a last preview build, LPX13D, for the Nexus 5
and Nexus 7 (2013) Wi-Fi. The APIs were final at API level 21, and Google
Play accepted apps with targetSdkVersion 21 from that day. The system image
for users was still two weeks away.
The SDK added 32-bit and 64-bit x86 emulator images, the v7 appcompat
library with the Material theme for older versions, the v17 leanback
library for TV, and NDK r10c. Google warned that “APIs have changed between
the preview SDK and the final SDK”: apps built against the preview had to be
recompiled, and the android-L packages deleted.
The LPX13D images had no OTA: the device had to be wiped and reflashed, and Google said they “only have the minimal apps pre-installed”. To receive the consumer update in November, the device needed a factory image again. GSMArena reported the build the same
day.