We went for a walk for a while and have our cell phones for 1 day not charged at times to see how fast and how well do the solar cells. After a while, we then found a place where we made our son a little picnic and there then these solar cells have ever tried. So small pocket out, unfolded, USB pure, oriented to the sun and mobile connected. My phone had load a charge of 39% and that of my wife of 44% before. We have about one and a half hours of sun getank and I was pleasantly surprised. My phone had 69% charge and my wife again whopping 74% charge. With such a small utensil I think is already a very good performance. So you can say good for 4 - 5 hours, can charge as a modern mobile phone. I do not know now how it looks with other devices but I will also test with a USB speaker. Let's see if the 8 Watt also rich here and I will write an update. So far I am very satisfied with the device.
However, some small negative I have to say. Once clouds are there listening to the device to load. Here lacks either the memory or I did not let the part lying in the sun long enough. Will I also try yet. If only it stores the energy I give 5 stars.
Conclusion: the much traveling for people who go on vacation to the beach or other outdoor activities make just a great utensil. You can do it comfortably in a backpack because it is very compact and it can also be taken anywhere else. The design is modern and the pocket a small eye-catcher because no one expects what is hidden in it. A little pricey but a clear recommendation, it is worth to me.