Landscape mode For iOS only(for now)
(May cause difficulty in catching pokemons)
Step 1: Fire up Pokemon Go and turn your iPhone into landscape mode and keep it in that orientation throughout.

Step 2: Tap the Poke Ball at the bottom of the screen.

Step 3: Tap Settings in the corner of the screen.

Pokemon-Go-settings

Step 4: Scroll down and tap “Report High-Priority Issue.”

Pokemon-Go-landscape-2

Step 5: Tap “Yes” when asked if you’re sure that is exactly what you want to do.

Pokemon-Go-landscape-3

Step 6: Your iPhone will then be kicked out into Safari to load the Pokemon website. We don’t actually need that, so press the Home button.

Step 7: Fire Pokemon Go up one more time and marvel at its landscape-ness.

Source: http://www.redmondpie.com/how-to-play-pokemon-go-in-landscape-mode/
-Admin Pochama