Its been said I suffer from battery paranoia, having always got the ability to charge a mobile

Totally concur and for those who are the iPhone with its non removable battery take a look at the Mophie juice pack air and plus, which achieve exactly the same effect. Meaning like me you can leave your hotspot on and everything else on and still get through a long day with battery to spare!

When all else fails take a look at the TeckNet iEP380 5000mAh battery packs from Amazon for juicing up your tablet and mobile phone!