The first thing you should do is reboot your iPhone or iPod. Like a computer, sometimes the phone needs a good reboot. The easiest way to do this is to hold down the button on the top of your device, until a screen with a red slider that says 'slide to power off' appears. Slide the slider to the right and wait for the phone to power down, then press the button on the top of the device to turn it back on.
If a particular application is giving you grief, you can try removing and reinstalling the application. You should be near your computer with iTunes installed to attempt this. On the home screen on your device, hold down the MENU key at the bottom of the device, until you see the icons 'jiggle'. Then, find the icon for the application you want to remove and tap the (X) on it's icon. Follow the prompts to remove the application. Once you have done that, plug your device into your computer and start iTunes if it isn't running. On the sidebar, click on your device, then click Applications. Make sure the application is ticked in the list, then click the Apply button at the bottom right. The application should be installing.
You may also want to check for updates to applications. You may be running into a bug with the application that the developer has already fixed. You can do this either from the App Store on your device, or on a computer with iTunes.
iTT Perth's Find Nearest Stops feature uses the Core Location API's introduced in iPhone OS 2.0. Since the iPod touch does not have a GPS receiver, this function will not operate correctly. Core Location will use the location of the mobile phone towers you are connected to, before checking with the GPS. If you are indoors, or in a place with a weak GPS signal, your location may not be as accurate, and distances may be measured from your mobile phone tower.
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