Not the 3g version but cheap for what it has been recently
The size of the device in millimetres.
Nokia Series 30+
The software that runs the phone. Different software has different features and strengths, so it's best to try out a few to decide which you prefer.
Battery talk time is the maximum length of time you can make a phone call using the device (under ideal conditions) before the battery needs recharging.Battery standby is the maximum length of time the device can remain switched on before the battery needs recharging. Standby time is theoretical and based on lab conditions.
Rear - Megapixels
The amount of megapixels (MP) the device's camera has. This is a measure of detail, so, as a general rule, the higher the megapixel count, the more detailed photos you'll be able to take.