Been using the app on a Samsung Galaxy S4 only for it to suddenly stop working a couple days ago. Uninstalled and wanting to reinstall thinking that might fix the problem, only to find out that is no longer an option. Consider me pretty bummed.
I hope there is a fix. Meanwhile you can still take photos with your phone, then transfer them to a laptop and add them to iNaturalist through the web browser. That’s the method I routinely use, and it’s much faster than submitting observations in the field through the phone.