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 Olympus XZ-2 iHS and Panasonic ZS20 side-by-side from the front, back and top in their relative dimensions. Olympus XZ-2 iHS has external dimensions of 113 x 65 x 48 mm (4.45 x 2.56 x 1.89″) and weighs 346 g (0.76 lb / 12.20 oz) (including batteries). Panasonic ZS20 has external dimensions of 105 x 59 x 28 mm (4.13 x 2.32 x 1.1″) and weighs 206 g (0.45 lb / 7.27 oz) (including batteries).
Below you can see the front view size comparison of Olympus XZ-2 iHS and Panasonic ZS20. Panasonic ZS20 is clearly the smaller of the two cameras. Its body is 8mm narrower, 6mm shorter and 20mm thinner than Olympus XZ-2 iHS.
Now lets look at the top view comparison of Olympus XZ-2 iHS and Panasonic ZS20.
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Panasonic ZS20 is significantly lighter (140g ) than the Olympus XZ-2 iHS which may become a big advantage especially on long walking trips.
Unfortunately neither Olympus XZ-2 iHS nor Panasonic Lumix DMC-ZS20 (Lumix DMC-TZ30) 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
Olympus XZ-2 iHS and Panasonic ZS20's LCD screens has the same diagonal size of 3".
On the other hand, Olympus XZ-2 iHS features a Tilting screen
where you can change the angle of the screen to make it easier to shoot from waist or over the head levels whereas the Panasonic ZS20 has a fixed type screen which provides less flexibility in shooting positions compared to XZ-2 iHS.