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 Panasonic ZS3 and Casio EX-H15 side-by-side from the front, back and top in their relative dimensions. Panasonic ZS3 has external dimensions of 103 x 60 x 33 mm (4.06 x 2.36 x 1.3″) and weighs 229 g (0.50 lb / 8.08 oz) (including batteries). Casio EX-H15 has external dimensions of 101 x 60 x 28 mm (3.98 x 2.36 x 1.1″) and weighs 161 g (0.35 lb / 5.68 oz) (including batteries).
Below you can see the front view size comparison of Panasonic ZS3 and Casio EX-H15. Panasonic ZS3 has the same height with Casio EX-H15. On the other hand, with a width of 103mm, it is 2 wider and also with a thickness of 33mm, it is 5mm thicker than Casio EX-H15.
Here is the back view size comparison of Panasonic ZS3 and Casio EX-H15.
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Casio EX-H15 is significantly lighter (68g ) than the Panasonic ZS3 which may become a big advantage especially on long walking trips.
Unfortunately neither Panasonic Lumix DMC-ZS3 (Lumix DMC-TZ7) nor Casio Exilim EX-H15 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
Panasonic ZS3 and Casio EX-H15's LCD screens has the same diagonal size of 3".
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.