These newer manufacturers adopting Android (although not necessarily basic Android) include Chinese smartphone vendors ZTE, Xiaomi, which recently hired Google executive Hugo Barra, and Yulong, which makes Coolpad smartphones like the Quattro 4G that ran Android 2.3 (Gingerbread) when it launched in late 2012 in the U.S.
Other Nexus benefits
Google not only has set the stage for this smaller-vendor manufacturing process with the Nexus series, it has set up greater value for the 1 million apps in the Google Play store, which become available to more buyers as Nexus sales increase.
In addition, selling unlocked Nexus devices has, to some extent, empowered buyers. They can have a choice of a carrier -- assuming the device's cellular network will work with various carriers. This more open approach is widely used in Europe and other regions where GSM wireless dominates, but now LTE is becoming a common wireless connection across major U.S. carriers as well.
Some wireless carriers won't give a full range of services and apps to customers who use unlocked Nexus devices and then buy a carrier's SIM card for cellular connectivity. "Will the carriers allow you to use any app you choose, or will they require that you download some specific app, such as their videoconferencing service? It's a gray area," Gold said.
Even with some limits placed by carriers on Nexus usage, Google seems solidly on track to add more Nexus smartphones and tablets in the future. The roadmap is not public, however.
Nexus-Android pushes emergence of Tizen
Google's Nexus approach has helped challenge wireless carriers that fear the overall growth of Google and have pushed for big device makers like Samsung to find alternatives to Android.
Tizen, an open-source operating system that attracted attention at Samsung's recent developer conference, has emerged as a potential challenger to Android, and therefore to Nexus products.
"Tizen is a hedge against Android's strength," Moorhead said. "Carriers know that there are certain buyers that want an unlocked phone like the Nexus, and as long as that number remains small, the carriers are OK. But I think carriers are concerned that Google is getting too powerful, which is why they are interested in Tizen in the long term."
Four years into the life of Nexus on basic Android, it's ironic that Android was originally seen as the disrupter to other dominant smartphone operating systems. "Funny how Android was originally a hedge [against] Microsoft, BlackBerry and Nokia," Moorhead said.
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