Idealpoint via Amazon offers the New Trent iTorch 5,200mAh External Battery Pack and Charger, model no. IMP52D, for $29.95. Coupon code "TRENT52D" makes it $19.95. Plus, Prime members receive free shipping. (Non-members can spend $35 or more to get free shipping; otherwise, it costs $5.74.) That's $50 off and the lowest total price we could find. (For further comparison, we saw it bundled with a 12,000mAh charger for $50 more a year ago.) This battery pack is compatible with a large number of iOS and Android devices.