i have an i pod touch 3rd generation but it tells me this app requires iOS 4.3. what do i do?

Welcome to Apple Support Communities

A 3rd generation iPod touch supports iOS 5.1.1, so you can update your iPod. Connect it to your PC or Mac with iTunes and it will make a backup automatically, and then, follow these steps to update in iTunes > http://support.apple.com/kb/HT4623?viewlocale=en_US&locale=en_US

If you are running iTunes 11, the device will appear under the toolbar, so choose it and press Check for Updates. If you are running an older version, choose it in the sidebar and select Check for Updates

See the chart below to determine whether you can upgrade your device and what you can upgrade to. If you do not have a Software Update option present on your iDevice, then you are trying to upgrade to iOS 5 or higher. You will have to connect your device to your computer and open iTunes in order to upgrade.

IPhone, iPod Touch, and iPad iOS Compatibility Chart

Device iOS Verson

iPhone 1 iOS 3.1.3

iPhone 3G iOS 4.2.1

iPhone 3GS iOS 6.1.x

iPhone 4 iOS 6.1.x

iPhone 4S iOS 6.1.x

iPhone 5 iOS 6.1.x

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iPod Touch 1 iOS 3.1.3

iPod Touch 2 iOS 4.2.1

iPod Touch 3 iOS 5.1.1

iPod Touch 4 iOS 6.1.x

iPod Touch 5 iOS 6.1.x

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iPad 1 iOS 5.1.1

iPad 2 iOS 6.1.x

iPad 3 iOS 6.1.x

iPad 4 iOS 6.1.x

iPad Mini iOS 6.1.x

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Select the method most appropriate for your situation.

Upgrading iOS

1. How to update your iPhone, iPad, or iPod Touch

2. iPhone Support

3. iPod Touch Support

4. iPad Support

a. Updating Your iOS to Version 6.0.x from iOS 5

Tap Settings > General > Software Update

If an update is available there will be an active Update button. If you are current,

then you will see a gray screen with a message saying your are up to date.

b. If you are still using iOS 4 — Updating your device to iOS 5 or later.

c. Resolving update problems

1. iOS - Unable to update or restore

2. iOS- Resolving update and restore alert messages