Since the zotero app for Android never became available, I decided to develop a third party app based on zoo for zotero myself. Although I know you guys are working on an official Android app application, I can't wait for it at the moment. I wanted to ask if I could get involved in your development work, but my current development level is not very good. If so, would you mind giving me your email so that I can quickly communicate with you about any problems I encounter?

I'm currently having problems locating the annotations in the pdf.
I have found the annotation information in zoo for zotero's database, and the code for its location is:
position={"pageIndex":6,"rects":[[291.987,28.88436708860779,560.6143594936708,291.48400000000004]]}

But I do not understand the meaning of these numbers, it seems that it is in the order of left, bottom, right, top. Are these numbers the actual position of the corresponding page in the pdf, and are there any functional conversion?

I have observed that the coordinate system you are using has its origin located in the lower left corner rather than the upper left corner. Is my understanding correct?

I am looking forward to your reply.