Moodle custom mobile application white screen Issue

I am trying to customize my Moodle mobile app. I done all the process in github and phonegap. my phone shows a white screen while starting itself. I added repository url and did ready to build in phonegap and download android apk file and transfer that file into my mobile and installed apk file successfully but when i open that app showing white screen. my github repository: https://github.com/mohdmazharkhan/moodlemobile2.git branch : master And Also I tried to build moodle mobile app using android studio but option only not showing for generate signed apk file, please follow below image. [![enter image description here][1]][1] And one more thing I have to tell my manager told don't use github because our files online will not save use android studio or some other offline tool. Please help me to out this issue. Thank you very much [1]: https://i.sstatic.net/F2XjI.png