1. Whatever you do, change only one thing at a time. If that change interferes with scripts that are necessary to run in order for your website to function the way you intended, then you will immediately understand what caused the problem.
To illustrate that: if you were thinking of installing a new plug-in, install the plug-in and then look at your page, and then activate the plug-in, and then look at your page again to see what that actually does.
If everything is working smoothly, you can install and activate the next plug-in.
Make sure that your page is at the safest URL which is no longer HTTP:// but rather HTTPS://. I was unaware and ignored that for the longest time and only noticed because of error logs that my site was not secure and that might also happened to the visitors to your site.
Update the settings in settings/general when accessing the site in your desktop environment. That way you can avoid being rejected while trying to connect to the server from your hand held. Otherwise deinstall or deactivate recently changed plug-ins (see 1.)
When you have a self hosted blog with an independent hosting server provider other than the blogging services that are available with word press and Blogger for example, then you can be almost sure that that hosting provider has an SSL running to protect your word press installation and your site. If you are under the impression it’s not working properly, do contact your hosting provider for support.
Think twice before installing firewalls or an SSL plugin from your wordPress app … Any app that acts like a server might have unwanted impacts on the operation of your site.
4. My personal set up experience
Not sure if that’s related to certain version limitations but in my experience there was no way of manipulating the exact URL of the site that I was adding to my WordPress app on iOS 12 on iPhone 7 Plus. When I was logged in my WP interface in my desktop environment, I was able to change URl, and that was populated into the app on my handheld within 12 hrs, most likely faster than that, but that is when I checked first today and noticed.
To reinstall the app might be a way to update URL with smart phone access only, and also,
The app links to WP settings by external login via the onboard/default browser – can we change that by making the browser of choice the default device browser?
The whole arrangement begs the question, if it weren’t less complicated to just pull up your mobile browser, navigate to your site and login?!
What I’m also missing dearly is a way to manipulate widgets from within the app. Please elaborate, feels like I am missing out on something.
So far it’s been a bit of a sobering, my app installation experience, trying to migrate all the business operation away from stationary environment to handheld devices.
Altogether it’s been inspiring though as application development has come a long way since I tried this last just about five years ago, and plug-ins are usually working great and are very useful at keeping maintenance with your site manageable.