Demolition can complete a level instantly. Create a word of at least four tiles to get a red demolition tile. Then, make a word of at least seven letters to get a gold demolition tile. If you are able to make longer words, this will result in more points.
Gems
Gems are the game's premium currency. You can earn free gems through the in-app purchase screen. Scroll down to the offers. You can earn free gems by liking or following the game on Facebook and Twitter or you watching advertisement videos.
Oxygen
Take note of your loss of oxygen. After losing all your oxygen, you have one of your characters pass out before completing the level. Make sure that you connect at least one word with a blue tile to your character when you pop an oxygen tile.
Unlimited lives
You have a maximum of five lives at a time. After you lose those lives you normally have to wait for them to be restored over time. However, you can regain them instantly by advancing the time on your device. Afterwards, set the time back to its correct value.
Demolition...