How many will it have happened, at least once, that the smartphone or tablet has downloaded at the very best moment, perhaps while you were about to send an important text message or an "email? And how many have happened not to be able to make a phone call. back from work or from a busy day, because the display of your device has signaled "low battery"? After all, it is a great classic of technological accessories, from smartphones to GoPro!
The battery of the smartphone, as well as that of the tablet, is increasingly subjected to heavy loads (internal capacities, downloaded apps, device functions), so it is useful to always carry a portable charger with you.
The so-called power banks are those accessories, more or less small, that allow you to recharge your phone or tablet without the need for a power outlet. But before buying them you need to know some features: