If I'm honest: Charging via USB is for me partly a closed book. I specially bought myself a small USB-meter for voltage and current, to find out why the store sometimes "back takes a little longer". As the main culprit I could so after all, ever identify the charging cable, the partially loaded only with minimal power. Under maybe 20 different cables were just 2-3 left, showed good values. Short cables with thick cross-section are to be preferred, but there are also exceptions. Even and especially "original cable" that come with the tablet or the smartphone, do not guarantee fast loading times.
But also my tablet so I could expose a bitch, which loads only fast if the USB cable already is under tension when plugging. Maybe I will one day have to understand the extent to which equipment and loaders "entertain" a suitable cable as to which is the appropriate charge current and probably why the charging current is changed from time to time in both directions.
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The advantage of this variant lies in the charger (removable) power cord; the use is simple variable and hideaway as if cables and equipment decorate the vicinity of the wall socket. Especially since this device is indeed designed discreet but rather exudes earthiness. What indeed does not have to be bad: With silicone feet the charger is ever quite slip. And when the performance is top - at least compared to all the things I otherwise available. To run the Ipow its limits, I had (via meter) already two devices attached to a port, in order to reach the maximum: 2.8 A are possible in this case, that's class and significantly more than indicated! It is as with most devices not matter which port you used - the different labels with 1 A and 2 A are again only to to document the maximum power of 25 W by calculation.
Further pleasing: The unit is largely silent - only at full load, there is this typical buzzing, but even barely audible. The heating keeps me within the normal range.
Those looking for no design part - there is some really smart charger - but a very current thirsty tablet or smartphone has that possibly can load with more than 2 A, which can not go far wrong here.