The business of reading from my iPad and getting a temporary banner across the top of the display that you have sent me an email is referred to by Apple as "notifications". The iPad handles them pretty well as far as I am concerned. Your message in snipped form appears temporarily at the top of my screen for about 5 seconds, which is long enough for me to see it is from you and the jist of what you wrote. Then, it fades away.
Just like my secretary, the iPad can be set to not notify me of anything, period. Or, what I have described or it can also play a sound to alert me.
If you get hurt or are arrested in a foreign country and need bail money, I want to be notified. Depending on what I am doing at the time, I may be able to go right to the airport to start getting to you or I might have to wait until tomorrow. If you are in South Africa and all flights there are cancelled or booked or blocked by volcanic ash, it may be several days or more until I can get there. Depending on the nature of the notification, I might simply email or text my sympathies back. I might get so upset and focused on your problem, that I turn off all notifications and turn off all phones, shut down all contacts no matter what other issues or problems occur in my world and friends.
I used to think my boss should mark out a section of his calendar "Busy - not to be disturbed" for 15 or so minutes a day, just for himself and his sanity. I do care for you but I don't just wait phoneside for a call or tablet-side for a notification of what you are doing. That means that 96% of the time, special messages from you will be interrupting something I am already doing. I won't consider them very intrusive unless they go on too long or are about problems that strike me as too small or too big for me to handle.
Corporations, branches of the government and some relatives tend to feel that everything they want me to know and attend to are top priority. Somewhere, E.B. White wrote about the local elementary school getting a public address system installed and warned that the administrator would start thinking that every item was sufficiently important to interrupt the classes with an announcement. He wrote about that somewhere about 1938. He might be surprised at interruptions, often intrusive ones, we allow today. I heard of a wedding where the groom interrupted his own wedding to take a phone call.
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