FYI, if you need to detect that the app is opened inside Hive (as opposed to a normal web browser), I've added a custom user agent string - inside Hive, navigator.userAgent will now include "Hive/0.9" (or whatever the version is) at the end. I'd say there should be very few cases where the user agent will have to be checked in code, but it's there if you need it. (This is only available in testing releases now, see GitHub releases page.)
I've also fixed the problem reported by @knowitnothing:
There seems to be some problem regarding overwriting a running application, which causes the bitcoin object to disappear. I can reproduce this every time by doing the following:
1) Create your app X and run it inside Hive;
2) While it is running, overwrite it (i.e. open myappx.hiveapp and confirm the overwrite);
3) Right click and click on Reload;
4) Right click and click on Inspect;
5) The bitcoin object is gone
How to fix the missing bitcoin object: restart the app.