Battery life is the number one concern when people think about buying a new smartphone, to the point that if a phone had nearly double the longevity of even the most expensive flagship handsets, it would be easy to overlook some of its faults. But at some point deficiencies start to drag down the novelty of having a really big battery, which is precisely the problem with the Asus ZenFone 4 Max. This thing has one of the biggest batteries you can find in a smartphone -- and it's only $US200! Yet budget components take all the fun out of it.