48 hours of regular Nexus One use; always on, no charging. That’s what JuiceDefender (free) and its partner app, UltimateJuice (€2.79; $3.76 at the time of this writing) have done for me. JuiceDefender, on its own, is a great app. With it, you can set up a profile that will determine under what conditions your data connection will be active and for how long. For instance, the most simple setup is to schedule your APN to connect, say, for one minute, every 15 minutes. But there’s plenty more that can be done with this software from Latedroid. Perhaps you want cellular data to be disabled from 2:00 AM to 10:00 AM. Why not shut data down when your battery is down below 3% of capacity? Maybe you want these rules overridden when the screen is on so you can manually refresh your GMail. JuiceDefender can facilitate all of this and more for you. But if you really want to take advantage of the program’s full potential, you’ll need to install UltimateJuice, which is really just a premium app that unlocks JuiceDefender. With both installed, you can enable all of the same rules for Wi-Fi, plus disable the search for networks when you’re not near any networks. Sure, you could enable and disable Wi-Fi manually via the Power Control widget, but will you remember to? Really? I don’t, which is one of the functions that make this app such a great value for me.