Via an unofficial port of Xperia Z2's camera application
Owners of Sony Xperia Z1 and Xperia Z1 Compact devices can now enjoy 4K video recording capabilities on their handsets, courtesy of an unofficial port.The Japanese mobile phone maker has included 4K video recording inside its Xperia Z2 smartphone, and some enthusiasts have decided to bring the feature to other devices as well.
Thus, an unofficial port of the Xperia Z2 camera is now available for Xperia Z1 and Xperia Z1 Compact handsets courtesy of XDA-Developers, allowing the owners of these phones to enjoy not only 4K video recording but also providing them with Timeshift capabilities.
The port does not appear to be in final version as of now, but it should work pretty good on said devices. Steadyshot in 4k video app does not work at the moment.
Those who would like to try the feature on their smartphones should head over to this thread in the XDA-Developers Forum to learn more on what it has to offer.
One thing that they should keep in mind when considering the installation of the port is the fact that their handsets need to be rooted, deodexed, and with no other camera modes installed on them. The port does not work on Xperia Z as of now.