Jar on a Bar (iPhone iPod)
CheatingDome.com
Various Game Hints
You can use blocks to push away other blocks, and this is sometimes useful when you want to create a solid landing platform below your jar.
Avoid putting the jar too close to the edge of a block - even the slightest movement is likely to send it crashing over the side.
You earn shells after each level and these can be used to purchase one-use items which aid your progress on more difficult levels.