The airmap is only the first step, you have to then go to the dji website and apply for the self-unlock, and then show the confirmation message you got from airmap... And then you have to download and import the codes over to your aircraft. It's a multi-step situation....
360 panorama is in the stock DJI GO4 app for Spark, no 3rd party app or special processing needed. Here's a tutorial how to do it, and share it online.
OTG cable replaces the need for WIFI. You can turn WIFI completely off on your phone while using OTG cable, thus reducing any potential interference. I have way better luck using OTG cable, definitely worth the $9.
Ive been moving to cloud storage, you can transfer wirelessly to your phone without removing the sd card at all, and let phone upload to your photo cloud account service when you're back at Wi-Fi.