Most of the times JuiceDefender will work just fine out of the box with “regular” radio streaming apps like WinAmp. This is because JuiceDefender never cuts connectivity while there’s an ongoing data transfer – it always waits for network activity to finish before disabling your phone radios.

However some music streaming apps – notably Pandora – don’t always play nice with this safeguard (if you’re curious about the technical reason: they cache an entire song as quickly as possible, subsequently halting network traffic until the next song).

But don’t worry, the Apps trigger is there to save the day: this feature allows fine-grained connectivity control on a per-app basis. You can use it to instruct JuiceDefender to leave connectivity enabled while specific apps (e.g. Pandora) are running – even when the screen is off.

The Aggressive and Extreme profiles include the Apps trigger in the Status tab (scroll down a bit). If you are using the Balanced profile and want to use this feature, you’ll have to activate the Customize profile – you will then find the trigger in the Settings tab. If you’re using the Advanced profile, you can find it in the Triggers tab.

Once you spotted the Apps section, tap on Configure apps. A list with the installed applications will appear – scroll around until you find Pandora (or whatever music streaming app is giving you trouble) and tap on its entry until the button on the right reads Enable/screen off. Voilà !