Your apps are tied to your Roku account, not your Roku device, so as long as you link your new TV to the same Roku account all of your apps will be automatically installed. Just in case you're not sure what email you used for your Roku account, you can see it under Settings->System->About on your Express. The apps will show up in a random order, so you may have to rearrange them. You may also have to sign in to some apps with the email address and password you used for that app. Any subscriptions/purchases you have through Roku should just work on the new TV.
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