Stitch dual-fisheye image captured by Theta Z1. To get the DNG file onto your phone, you need to use the mobile app for DNG file transfer, which is free and available for iOS and Android. People often use this with the free dual-fisheye plug-in for Z1.
Check out this video by Guo Yuqing
Z1 Stitcher Lens Calibration Guide
Z1 Sticher working on iPhoneSE
Z1 Stitcher and DNG Transfer Available for iOS
THETA Z1 DNG Mobile Workflow with Ichi Hirota Stitching and Transfer Apps