At its rather exclusive ARM Tech Day 2014 in Austin, the British company has given us more details on the future of its mobile efforts -- in specific, its upcoming Cortex-A53 and -A57 CPU cores. ARM also said that, after passing the the $60 mark last year, the cheapest Android phones will be just $20 "in the next few months." According to ARM, these cheap devices will cause the low- and mid-range smartphone and tablet markets to more than double over the next five years, resulting in almost 2.5 billion total mobile device shipments by 2018... and they'll (probably) all use ARM chips.