For this, the Lumia 820 has but two big advantages:
1. Internally put 8 GB of disk space. But this may be increased by Micros SD to another 64 GB. Enough space for music, photos
2. The battery is equipped rather mediocre at 1650 mAh. For this you can replace the battery.
Otherwise, there is nothing to complain about. Phone Winndows known runs smoothly and supple. So far, no crash. The device is absolutely reliable and with 4.3 "screen, it is not too large and fits comfortably in your Hand.Ein faithful companion who does not let you down. Absolute buy recommendation for this excellent smartphone in the middle class.