I'm looking into charging my iPad using solar energy. Is the best option the Joos Orange or can anyone recommend an alternative charger? I like the idea of letting the sun charge a battery and then using this battery to charge my iPad. This way I could leave the charger in the sun for a couple of days and then charge my iPad which needs charging about every four days. To be honest, I don't know where to start. So if anyone has any pointers, that would be great. Price and size isn't important, I just want something that works. Thank you!