Keep tracing Bitcoin exchange rate. Application will inform you (with sound or vibration) when exchange rate will rise above or falls below the set value. You can also set how often app will be connecting mt.gox to sync the rate.
At this moment app supports only mt.gox exchange rate.
You can support us by sending some coins to: 1645GssNfJaQkxEYVrfd5s95KQMgNkpFAa