BitcoinTicker.com is a compilation of Bitcoin tickers, apps, and widgets.
What determines the price of Bitcoin? The free market determines the price. There is generally not liquidity between different exchanges so you will often see large discrepancies between different exchanges.
Is the Mt. Gox the primary exchange price? The Mt. Gox was historically the primary exchange rate for Bitcoin. However, withdrawals are limited for some countries so that price may not be available to many traders. as a result, the Mt. Gox price is often higher than other exchanges.
Can I get a Bitcoin Wallet for iPhone iOS system? No. apple will not allow those apps but some ticker programs are available.