1
In this moment, most people have a computer or a smartphone.
Nowadays, most people have a computer or a smartphone.
At present, most people have a computer or a smartphone.
Use nowadays to talk about the present period, especially when comparing it with the past: ‘Nowadays, people spend more time online.’
At present means ‘now’ or ‘currently’: ‘At present, the service is only available in Europe.’
2
I am unemployed in this moment.
I am unemployed at the moment.
Use at the moment, not in this moment, to mean ‘now’: ‘I’m busy at the moment.’ ‘She’s talking on the phone at the moment.’
3
In that moment, she looked through the window and saw him.
At that moment, she looked through the window and saw him.
Use at that moment when you mean ‘then’ or refer to a particular point in time: ‘At that moment, the phone rang.’
In that moment is possible when we describe what someone felt or experienced during a particular moment: ‘In that moment, I felt completely alone.’ ‘In that moment, everything seemed possible.’