Fragen über die Beispielsätze mit, und die Definition und Benutzung von "Smartphones"

A: G2G -got to go
Lmao- laugh my ass off
Lol- laugh out loud
Smh- shake my head

A: Essentially, those have the same meaning

A: They all mean the same thing. The first two both sound very natural. The third one is a little old fashioned (using "but for").

A: There isn't much of a difference, mostly "smartphones on which small children can learn the alphabet" would mean that they can use the phone itself to learn the language, and "smartphones with which small children can learn the alphabet" could mean that the phone helps them learn the alphabet, again not much difference at all really

A: I'd use "with" there instead. You can google it with quotation marks to find out how people prefer to say it. So "pay by your smartphone" - about 23'000 hits, "pay with your smartphone" - about 200'000 hits.

A: Schaue nach der Frage, um die Antwort zu sehen

A: Can you give more detail?

It sounds like this is a sentence in the middle of an essay and you have more to say after this sentence. Maybe instead of at last, I would say finally.

A: そうですよ！is likely toは正しいだけどね

A: both positive and negative impacts

A: "All of us are playing with our smartphones at dinner"

But I think
"All of us are playing with our smartphones during dinner"
"All of us are on our smartphones during dinner"
would be better alternatives.

A: People use smartphones for playing games, checking social networks and so on. Everyone is usually looking down at their smartphones as if they were dead sunflowers.