Speedx objective is to survive as long as possible, player have to avoid collision with obstacles or track edge. During run player can collect bonuses, each bonus has unique properties.

Challenges

PvP challenges (player versus player) allows player to compete with each other. Player can Create Challenge by selecting difficulty and setting stake, newly created challenge can be either open (any player can undertake it), or direct (opponent has to be selected from Open Feint friends list).
Player can accept challenge from Find Challenges dialog or review PvP challenges in Challenges History dialog, for any lost challenge one rematch may be scheduled by tapping on challenge entry in Challenges History dialog.

Challenge state

Direct challenge

Direct challenge against one (or created by) of your friends from Open Feint

Open challenge

Open challenge, anyone can accept it.

Rematch

Direct rematch challenge

Direct challenge

Open challenge with rematch scheduled

Upgrades

Player can acquire upgrades which help playing the Stages and Survival (in Casual, Easy and Normal difficulties) mode. Upgrades can be bought (when unlocked after finishing certain number of races in Stages mode) with in-game currency Credits (Cr), available through Tapjoy offers network or in-app purchases.
Upgrades can be either always available (like additional shield slot) or may require activation. Active upgrades are activated by tapping on its icon displayed on left side of HUD.

Bonuses

Shield (orange spot)

Shield can be used to destroy obstacles, single shield unit can be used to break cube obstacle, to destroy beam two units are required. Shields depletes with time. Player can hold up to three (or four if appropriate upgrade is acquired) shield units.

Quake (red spot)

Destroy all visible obstacles when activated.

Time dilatation (blue spot)

Slows down the game and freezes all moving obstacles.

Space fold (green spot)

End hazard zones when activated.

Hazard zones

Blackout

Tunnel is rendered in negative, during this hazard obstacle trails are not visible.

Gravity well

Visibility during this hazard is very limited moreover vision is distorted and external force is applied so player has to adjust movements.

Dark nebula

Block are rendered in negative, tunnel intensity changes over time.

Hue shift

OMG, it's full of... colors.

Plasma cloud

Player can encounter plasma vortex here, collision with such obstacle will consume one shield (if available) and reset bonus.