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 Pentax H90 and Olympus XZ-10 side-by-side from the front, back and top in their relative dimensions. Pentax H90 has external dimensions of 101 x 65 x 28 mm (3.98 x 2.56 x 1.1″) and weighs 153 g (0.34 lb / 5.40 oz) (including batteries). Olympus XZ-10 has external dimensions of 102 x 61 x 34 mm (4.03 x 2.41 x 1.35″) and weighs 221 g (0.49 lb / 7.80 oz) (including batteries).
Below you can see the front-view size comparison of the Pentax H90 and the Olympus XZ-10. Pentax H90 is 1mm narrower and 6mm thinner than Olympus XZ-10 but it is also 4mm taller.
Here is the back view size comparison of the Pentax H90 and Olympus XZ-10.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Pentax H90 is significantly lighter (68g ) than the Olympus XZ-10 which may become a big advantage especially on long walking trips.
Weather Sealing
Unfortunately neither the Pentax Optio H90 nor Olympus Stylus XZ-10 provides any type of weather sealing in their bodies, 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-10's 3.00" LCD screen is slightly larger than Pentax H90's 2.7" screen.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.