The budget friendly Nokia Lumia 521 for T-Mobile is now receiving the GDR2 (Microsoft) and Amber (Nokia) updates alongside the discontinued yet popular Nokia Lumia 810. The GDR2 (10327/8) update from Microsoft will bring new features like FM radio, call and SMS filters, improvements for Xbox Music and Internet Explorer, Data Sense, a resolution to the Other storage issue and more. Meanwhile the Amber component of the update comes from Nokia and adds new Nokia based features like Smart Cam, double-tap to wake, flip to silence and many more improvements.The update is generally pushed out in waves over-the-air (OTA) and you should receive a notification once it is available in your region for your device. If you have set updates to be downloaded automatically you should receive a notification once the update is ready to be installed on your device. You can also manually check for the update availability by heading to Settings > Phone Update > Check for Updates.
Make sure your battery is fully charged and that you are connected to a Wi-Fi connection before initiating the update, which should take around 10 - 20 minutes to complete. Once the update is completed the phone should restart one last time before it is ready for use.
The update is also being rolled out to the international Nokia Lumia 920 and the Nokia Lumia 928 for Veirzon.