Here is the full list of all 31 Canabalt achievements.
Find the Mothership
Find the Dark Tower
Find the Volcano Base
Find the Drill Fortress
Find the Dome City
Survive a jump into a hallway
Survive a Walker leg
Jump clear over a building and survive
Toss 50 obstacles out of your way
Run 21097m along the rooftops without dying
Run 42195m along the rooftops without dying
Run 21097m along the rooftops with two players
Run 42195m along the rooftops with two players
Complete the Defenestration challenge
Complete the Defenestration challenge with two players
Complete the Bombardment challenge
Complete the Bombardment challenge with two players
Complete the Purity challenge
Complete the Purity challenge with two players
Complete the Invasion challenge
Complete the Invasion challenge with two players
Complete the Fractured challenge
Complete the Fractured challenge with two players
Complete the Leap of Faith challenge
Complete the Leap of Faith challenge with two players
Complete the Panic challenge
Complete the Panic challenge with two players
Complete the Box Tripper challenge
Complete the Box Tripper challenge with two players
Complete each of the challenge districts
Complete each of the challenge districts with two players