Develop Reference

Copy text on handheld via tap in wearos

I am trying to build an authenticator sort of android app with support for WearOS , what i want to accomplish is ->
from a list of TOTPs if the user taps on any one of them ON THE WEAROS app , i want the OTP to be copied on my android handheld ( even when the authenticator application is closed)
is this possible ?

You should be able to communicate from your Wear App to your paired Mobile app using the Message Client.
https://developers.google.com/android/reference/com/google/android/gms/wearable/WearableListenerService
Your authenticator mobile app will be woken up when the wear app sends a message, and then handle it as you want.
See here for more information about data syncing. https://developer.android.com/training/wearables/data/data-layer

Notifications handling in apache cordova app

I'm building an apache cordova messaging app (using javascript).
I'm looking for a way to have more control over notifications in my app.
Is there a way to receive a notification and build its text on the client device? I would like to create it in the user's proffered language and use the user's contacts names in the notification itself.
Also, I would like to be able to decide if to show a certain notification when it is received in the device (for example, don't show a notification for a group chat that was silenced)
Is it possible to do when the app is not open at all?
How is it handled differently from native android and iOS apps?

We are talking about push notifications right?
I don't remember the exact function names but think it's quite possible using cordova notification plugin.
So when app is in active/background, you will be able to get the notification object in your callback and decide whatever you do - show it in notification area using local notification, or show in-app alert or just ignore.
When app is closed, system handles the notification and shows in notification area(based on the notification payload APNS/GCMS sends) and when user taps on it, app is launched and a notification handler callback is called inside app.
Anyway, I think what you want to do is quite possible with native apps and cordova plugin since it exposes all of native functionalities.

Can an app be build to send notification to non-app user

Is it possible to create an app that can send notification to the user who does not have the same app installed on his device.
I have come acrossed 'Push Notification' service via GCM and FCM but it requires the app being installed on both the devices to communicate or send notification.
(P.S- No suggestion for web application to user mobile service)

You can use other means of communication like SMS or email.

No. Notifications even though coming from Android Google servers are part of the app environment. So you cannot send an app notification to non app users. If that was the case imagine getting app notifications from Amazon and whatnot.
But you can use some other means like mail, sending links of your app via mail/sending invites via mail or SMS.

server update device not in use

I am developing a small chat application using node.js for iOS and Android, Now my question is that one user created a account and logged-in using this application from iOS or Android, then the user deleted this application without log-out. How the server knows this device has deleted the application without log-out?. Since, while user again installing this application, the push notification is still arriving without the user log-in.

Apple has a feedback service to give you information about failed remote notifications. Basically you listen the messages from feedback.push.apple.com and you flag the devices returned from feedback service. So no further push notifications will be delivered to that device. When user installs your app again you can remove the flag and start delivering the notifications.
For the android part check this question; Is there an Android GCM equivalent to the iOS Push Notification Feedback Service?

How to send a push notification from one Worklight-based Hybrid app to another Worklight-based Hybrid app

I run Push Notification Sample code on Worklight server and its working.
Now i want to send notification from one device to another device so what are the required changes in the adapter?
The adapter XML:
<displayName>PushAdapter</displayName>
<description>PushAdapter</description>
<connectivity>
<connectionPolicy xsi:type="http:HTTPConnectionPolicyType">
<protocol>http</protocol>
<domain>https://android.apis.google.com</domain>
<port>8080</port>
</connectionPolicy>
<loadConstraints maxConcurrentConnectionsPerNode="2"/>
</connectivity>
Should i change domain and port and i have to upload the app first on google play so that i can able to recive or send notifications. And should i create a key for android device on GCM

Push notifications in Worklight (and I believe at large as well) are not sent from one device to another per-se; consider it this way:
You have two applications:
A managing app
A receiving app
User A is running the managing app - this application is able to send a request to the server, which tells it to send a notification to some other user(s).
User B is running the receiving app - this application is able to receive notifications.
All of this is not related at all to the Google Play store.
Yes, both apps will require a GCM senderId and Key values in order to have any Push Notification capabilities.
As for implementing all of this... there is no sample to do this, but you already have part of the solution (the sample app is able to receive notifications). What you need to do now is have the managing application be able to retrieve a list of / specific username(s), and create a procedure that will invoke a function to send the notification based on the username(s) you have retrieved.