Due to endless problems and high consumption of various resources or components such as WiFi, Motorola has failed to fulfill his promise to bring Android stock quickly like a Google Nexus is involved. Despite it still not solved errors that Android Lollipop users suffer since its existence, Motorola has tried to optimize the firmware in the best way possible to try to prevent these problems with no impact to end users.
Therefore, and although the wait has been long, Motorola is slowly updating some terminals and making the leap to the latest version of Lollipop, the current 5.1 that theoretically partially solves some of the bugs, such as happened with the Motorola Moto X 2013. So serious it is that even some of the manufacturers decided to upgrade directly to 5.1 without going through 5.0.2, which is what has happened in the Motorola Moto G 4G first generation.
From operators and free users are seeing their terminals are gradually updating to the 23.21.17.en.EU version that offers Android 5.1 via OTA with the latest optimizations. And if you were still stuck in KitKat, since you can now enjoy the new Material Design interface with animation at 60 fps, Smart Lock, notifications on the lock screen and floats at the interface of the system, so do not disturb guest and multiuser mode, plus new settings and more accessible and interesting features such as flashlight or energy saving quick adjustments. The latter very successful in Lollipop, of course.
And if you have not received notification of a new firmware update, remember you can force it by going to “Settings” > “Phone Info” > “Update”. If at first does not appear be patience, it is a matter of hours it gets to your phone, because as usual it comes in stages, earlier for some and later for others.