Develop Reference

PWA launch icon update

Problem: my PWA is already installed on many clients, Android and iOS, and I want to update the launch icon and splash screen.
Android: according to Google documentation:
When the PWA is launched, Chrome determines the last time the local
manifest was checked for changes. If the manifest hasn't been checked
in the last 24 hours, Chrome will schedule a network request for the
manifest, then compare it against the local copy.
If select properties in the manifest have changed (see list below),
Chrome queues the new manifest, and after all windows of the PWA have
been closed, the device is plugged in, and connected to WiFi, Chrome
requests an updated WebAPK from the server. Once updated, all fields
from the new manifest are used.
Which properties will trigger an update? background_color, display, orientation, scope, shortcuts, start_url, theme_color, web_share_target
In my tests, when I update one of these fields in the manifest (I am updating background_color for Chrome to pick up the change and the images specified in icons\src with the new icon), it will indeed be picked up after some time (I can see it by navigating to chrome://webapks) but the launch icon will NOT be updated. I have tried changing the icon name in addition to the icon content but that does not help.
Notes:
if I follow the instructions in Testing manifest updates then the icon will indeed be updated after some time, but obviously, I can't ask this to my users...
My PWA is listed in the installed apps in Android's settings
iOS: here the icon is specified in an HTML tag apple-touch-icon and I could not find anything except this very old answer on SO:
In newer iterations of iOS, the Apple Touch Icon that is displayed on
the home screen is cached just like any other piece of content from the
website. By simply changing the name of the image, it will force the
home screen shortcut to refresh the icon the next time the shortcut is
launched.
<link rel="apple-touch-icon" href=".\icon.ico">
Again this is not what I am seeing, the icon will not change even if I modify the name of the referenced image.
What am I missing???

How to force a crash or delete an android application?

I have created an android app and now I cannot close it from my device.
I have set the app as default launcher and I have disabled the status bar(so I cannot access the settings menu). When I press the back and home buttons nothing changes because the app runs as a launcher.
Now I want to exit from the app and change the default launcher but I cannot.
Also my device is Viewsonic vsd224 (android KitKat 4.4 system)(all in one, it is not a tablet) and it does not reset to its factory settings from any combination of buttons when it is turned off.
I want to delete or crash the app or even reset my device but I cannot find a way.
Have you any ideas what I can do?(I cannot use android studio or any other IDE).

In Kotlin I would do something like this:
fun crashMyApp(){
throw RuntimeException("Crash my app!")
}
And call this method wherever you want to force the crash to happen.
Here's my inspiration for this answer.

How to detect that default launcher app is changed

I have developed an app which is working as a launcher app.
When the user removes my app from default launcher I need to know it.
User can remove my app from default launcher in two ways:
1. Settings->Apps->Reset app preferences.
2. Settings->Apps->My_App->Clear default launcher.
Please comment if anybody has any idea about:
1. How I can detect my app is removed from the default launcher?
2. Is there any listener/action for it?
3. Is there any way by which I can restrict/block clearing default launcher?
Thanks in advance!

Android keep my launcher as default

I am developing an android app for a company. Their employees must not use any other apps but the company-app,the preinstalled phone-app to make calls and the settings.
So I created a custom launcher and registered it as default. The launcher shows only the allowed apps. But the employees could open the settings and set the normal android launcher as default (and then use the internet for doing unallowed things or download malware) or uninstall my launcher.
Is there any possibility to prevent this without rooting? If I register the laucher as device administrator they could open the settings and disabling it.
Note: I have full access to the devices before they were delivered.
Best regards

I found a solution
1. I registered my app as boot-receiver
2. I created a service which tests which activity is in foreground (if it is from the whitelist: OK, otherwise: my app comes to foreground, blocks the foreground-activity and shows the user a warning "don't do this")
The next problem was: the user should be able to use the settings (for wifi), so he could uninstall my app.
3. Register my app as device admin (the user is unable to uninstall or force-stop my app until he unregister it as device-admin)
While testing which activity is in foreground, the service tests if the app is still device-admin. If it isn't device-admin, all apps were blocked until the app is device-admin again (the dialog pops up).

How can I update a home application without being asked to redefine the default home?

I have developed an application set as a home onto my Android device. On my device I set it as the default home application. That way, each time I click the home button, I am redirected to this app.
The problem I have is that I have to produce some updates. But when the app has been updated, the device ask to define the default home once anew.
I would like the update to be performed without the user having to define the default home again.

There isnt a way to do this. Each time your app is updated the user will have the opportunity to chose whether they want to keep it as the default home application. It is a means of Android showing a user he or she is in control of there device at all times.
If im wrong someone please correct me.