Is it good UX to show, or notify, users about deleted messages in WhatsApp?

Is it a good user experience for sender as well as the receiver of messages in any messenger app (here WhatsApp) to show that there were or was a message(s) deleted?
If I send a message to anyone and delete it before the receiver read it …
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What is the best place to put the delete button?

Well, this maybe the simple question but it has given me a headache for days.
I’m making an app, from design, code, etc…. The app is a note app, user can select multiples of them, and then can archive or delete them, it will look like th…
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Is UI Chips for all single choice input a good idea?

I’m working on an iPhone/iPad app that uses a lot of forms and we are currently using several different components for input where the user have to do a single choice from a defined list of items. For example:
Radio button in a list with …
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Error on initial push notification subscription

Does it make sense to inform the user with an error message when initial registration to push notifications fails?
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iOS and Android app – data download or page navigation first

What is the best perceived UX for mobile applications which require data downloaded midway through the journey. I cannot find this information online in Apple’s Human Interface Guidelines (or I am looking in the wrong place if so), nor Goo…