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 Canon ELPH 150 IS and Olympus E-PM2 side-by-side from the front, back and top in their relative dimensions. Canon ELPH 150 IS has external dimensions of 95 x 57 x 24 mm (3.74 x 2.24 x 0.94″) and weighs 142 g (0.31 lb / 5.01 oz) (including batteries). Olympus E-PM2 has external dimensions of 110 x 64 x 34 mm (4.33 x 2.52 x 1.34″) and weighs 269 g (0.59 lb / 9.49 oz) (including batteries).
Below you can see the front view size comparison of Canon ELPH 150 IS and Olympus E-PM2. Canon ELPH 150 IS is clearly the smaller of the two cameras. Its body is 15mm narrower, 7mm shorter and 10mm thinner than Olympus E-PM2. As you can tell, actually this is not a fair size comparison since Canon ELPH 150 IS has a built-in lens but Olympus E-PM2 doesn't. Once you put a lens on E-PM2, its thickness will increase significantly.
Now lets look at the top view comparison of Canon ELPH 150 IS and Olympus E-PM2.
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Canon ELPH 150 IS is significantly lighter (127g ) than the Olympus E-PM2 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 E-PM2, the total kit will weigh much higher.
Unfortunately neither Canon PowerShot ELPH 150 IS (IXUS 155) nor Olympus PEN E-PM2 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 Top Mirrorless Cameras with Weather Sealing
LCD Screen Size and Features
Olympus E-PM2's 3.00" LCD screen is slightly larger than Canon ELPH 150 IS's 2.7" screen.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.