[I should declare up front that the folks at Proporta are friends of mine and they are also part-time sponsors of The Phones Show. Opinions here are 100% unbiased though.]
The market for portable chargers is getting more and more crowded - heck, even Microsoft announced a range yesterday! Luckily, the need for them is increasing at a greater and greater rate, with quite a few modern phones still limited in terms of the battery getting through a full day.
Measuring roughly 12 x 7 x 1.5cm is only marginally heavier and thicker than a typical smartphone. All the corners are rounded and the front and back surfaces are soft-touch and wonderfully grippy. Even though the rim is aluminium-effect plastic rather than metal, the feel is still premium in the hand.
Inside is a 8000mAh Li-Poly battery. Using what we now know about battery physics, this is at 3.7V, i.e. the native voltage of the cells. By the time this is upgraded to 5V using circuitry, we're talking 6000mAh or so available for passing to your smartphones. I ran two cycles of tests across four smartphones and ended up with an estimate of 6100mAh available, so I was pleased overall.
Down at the business end are two standard USB outputs, one at 2.1A for tablets (or fast charging a phone) and one at 1A - both can be used at the same time. In fact, both can be used at once, while the Turbocharger 8000 is charging itself, i.e. functioning as a charging hub on your desk, which is quite cool.
Starting charging going requires pressing the little button on the top of the unit, but I prefer this over auto-sensing accessories, which always seem to be to be 'wasting' part of their store of charge in keeping an eye on the outputs. Four LEDs provide the traditional 0-25%, 25-50%, 50-75% and 75-100% indications of stored charge, plus they animate when charging is happening.
The accuracy of the LEDs seems good - in fact, they under-read, if anything. On competing devices, one LED often means that there's precious little left in the tank, while here just one LED lit seems to signify a very full last 25% and I managed to get about 2000mAh out of it, equivalent to driving the last 40 miles home with the petrol tank showing 'empty'(!)
I haven't raved about every Proporta Turbocharger design - I even rejected a few over the years - but the company now seems to be back on form with the 8000mAh Mohawk. It's the right balance between portability and capacity, being guaranteed to completely charge two smartphones from scratch (and possibly three).
Finally, the price of just over £25 (£30 on the site but knock 15% off with promo code LUCKYYOU) is in the right ballpark, considering the source and quality.