Battery life:
In rational use (telephone + email + web casual) battery takes between 2 and 3 days.
In use a little more thrust (intensive apps: games, gps etc ...) the battery holds a day.
Despite these perfs correct, I see a decline in the autonomy of about 20-30% since updated WP8.1 amber
Calls:
This is a laptop: the sound without the headset and passable (speakers)
Negative for me: the model I bought encountered many problems daccroche network sest however it improved significantly since the update WP8.1 amber
Pictures:
With good brightness, Zeiss loptique done some wonderful pictures. Indoor and low light, this is less good. Nokia apps offered are numerous and thoughtful, in short this is happiness!
Ergonomics:
Nice to handle, light, robust enough (fallen 2 times) malgrès its compactness.
Heater lot when we play, this is convenient in winter but a little unpleasant in the long run!
A small tendency to slide hands: clumsy provide a hull.
Screen:
This is not full HD but OLED screen is great: more than enough resolution for the screen size (4.5) blacks are deep, next dun lumia 635 the difference is huge! Touch interface is very responsive (compatible with gloves).
Performances:
For the web, email, photos, lOS, apps in general, everything is very responsive and pleasant to use.
If all installed games (8 asphalt for example) turn right, this is not a portable gamer, so when we play, it heats!