Size and weight are big decision factors when you are trying to find the ideal camera for your needs.
In this section, we are going to illustrate the Olympus TG-870 and Sony NEX-3 side-by-side from the front, back and top in their relative dimensions. Olympus TG-870 has external dimensions of 113 x 64 x 28 mm (4.45 x 2.52 x 1.1″) and weighs 221 g (0.49 lb / 7.80 oz) (including batteries). Sony NEX-3 has external dimensions of 117 x 62 x 33 mm (4.61 x 2.44 x 1.3″) and weighs 297 g (0.65 lb / 10.48 oz) (including batteries).
Below you can see the front-view size comparison of the Olympus TG-870 and the Sony NEX-3. Olympus TG-870 is 4mm narrower and 5mm thinner than Sony NEX-3 but it is also 2mm taller. As you can tell, actually this is not a fair size comparison since Olympus TG-870 has a built-in lens but Sony NEX-3 doesn't. Once you put a lens on NEX-3, its thickness will increase significantly.
Now lets look at the top view comparison of Olympus TG-870 and Sony NEX-3.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Olympus TG-870 is significantly lighter (76g ) than the Sony NEX-3 which may become a big advantage especially on long walking trips.
Again, this comparison may not be very useful in real life as we are comparing the weight of a camera with a built-in lens to the body-only weight of an interchangeable lens camera. Once you put a lens on NEX-3, the total kit will weigh much higher.
Weather Sealing
Thanks to the weather-sealed body of the TG-870, you can use this camera with more confidence under conditions where there is risk of exposure to water and dust compared to the NEX-3.
LCD Screen Size and Features
Olympus TG-870 and Sony NEX-3's LCD screens have the same diagonal size of 3.00 inches.
Both cameras feature
Tilting screens where you can change the angle of the screen to make it easier to shoot from waist or over-the-head levels.