Sony was the pioneer of compact-sized flagships when it first released the Xperia Z1 Compact back in the day. It packed the same flagship-level processor, the same flagship-level camera and the same flagship-level features like waterproofing, at a one-handed-friendly form factor.
Source: http://www.gsmarena.com/sony_xperia_x_compact_time_saver-review-1523.php
