Size and weight is a big decision factor when you are trying to find the ideal camera for your needs.
In this section, We are going to illustrate Nikon L31 and Sony T90 side-by-side from the front, back and top in their relative dimensions. Nikon L31 has external dimensions of 96 x 59 x 29 mm (3.78 x 2.32 x 1.14″) and weighs 160 g (0.35 lb / 5.64 oz) (including batteries). Sony T90 has external dimensions of 94 x 57 x 15 mm (3.7 x 2.24 x 0.59″) and weighs 148 g (0.33 lb / 5.22 oz) (including batteries).
Below you can see the front view size comparison of Nikon L31 and Sony T90. Sony T90 is clearly the smaller of the two cameras. Its body is 2mm narrower, 2mm shorter and 14mm thinner than Nikon L31.
Here is the back view size comparison of Nikon L31 and Sony T90.
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Sony T90 is 12g lighter than the Nikon L31 but we don't think this will make a significant difference.
Unfortunately neither Nikon Coolpix L31 nor Sony Cyber-shot DSC-T90 provides any type of weather sealing in their body, so you have to give extra care especially when you are shooting outdoors. If weather sealing is a must-have feature for you, check these sections: Top Compact Cameras with Weather Sealing
LCD Screen Size and Features
Sony T90's 3" LCD screen is slightly larger than Nikon L31's 2.7" screen.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.